Serialize and deserialize null (#783)

* Build (grpc's) nanopb with -DPB_FIELD_16BIT

We require (at least) 16 bit fields. (By default, nanopb uses 8 bit
fields, ie allowing up to 256 field tags.)

Also note that this patch adds this to grpc's nanopb, rather than to our
nanopb. We'll need to eventually either:
a) we instruct grpc to use our nanopb
b) we rely on grpc's nanopb instead of using our own.

(^ marked as a TODO for now.)

* Add some dependant protos

Imported from protobuf. Nanopb requires these to be present (though
anything using libprotobuf does not, as these are already built into
that.)

* Add generated nanopb protos based off of newly added proto definitions

* Build the nanopb protos

* Serialize and deserialize null

10 files changed, 797 insertions, 0 deletions

diff --git a/Firestore/Protos/CMakeLists.txt b/Firestore/Protos/CMakeLists.txt
new file mode 100644
index 0000000..f20f702
--- /dev/null
+++ b/Firestore/Protos/CMakeLists.txt
@@ -0,0 +1,45 @@
+cc_library(
+  firebase_firestore_protos_nanopb
+  SOURCES
+    nanopb/firestore/local/maybe_document.pb.c
+    nanopb/firestore/local/maybe_document.pb.h
+    nanopb/firestore/local/mutation.pb.c
+    nanopb/firestore/local/mutation.pb.h
+    nanopb/firestore/local/target.pb.c
+    nanopb/firestore/local/target.pb.h
+    nanopb/google/api/annotations.pb.c
+    nanopb/google/api/annotations.pb.h
+    nanopb/google/api/http.pb.c
+    nanopb/google/api/http.pb.h
+    nanopb/google/firestore/v1beta1/common.pb.c
+    nanopb/google/firestore/v1beta1/common.pb.h
+    nanopb/google/firestore/v1beta1/document.pb.c
+    nanopb/google/firestore/v1beta1/document.pb.h
+    nanopb/google/firestore/v1beta1/firestore.pb.c
+    nanopb/google/firestore/v1beta1/firestore.pb.h
+    nanopb/google/firestore/v1beta1/query.pb.c
+    nanopb/google/firestore/v1beta1/query.pb.h
+    nanopb/google/firestore/v1beta1/write.pb.c
+    nanopb/google/firestore/v1beta1/write.pb.h
+    nanopb/google/protobuf/any.pb.c
+    nanopb/google/protobuf/any.pb.h
+    nanopb/google/protobuf/empty.pb.c
+    nanopb/google/protobuf/empty.pb.h
+    nanopb/google/protobuf/struct.pb.c
+    nanopb/google/protobuf/struct.pb.h
+    nanopb/google/protobuf/timestamp.pb.c
+    nanopb/google/protobuf/timestamp.pb.h
+    nanopb/google/protobuf/wrappers.pb.c
+    nanopb/google/protobuf/wrappers.pb.h
+    nanopb/google/rpc/status.pb.c
+    nanopb/google/rpc/status.pb.h
+    nanopb/google/type/latlng.pb.c
+    nanopb/google/type/latlng.pb.h
+  DEPENDS
+    nanopb
+)
+
+target_compile_definitions(
+  firebase_firestore_protos_nanopb PUBLIC
+    -DPB_FIELD_16BIT
+)
diff --git a/Firestore/Protos/nanopb/google/protobuf/any.pb.c b/Firestore/Protos/nanopb/google/protobuf/any.pb.c
new file mode 100644
index 0000000..b28d0ba
--- /dev/null
+++ b/Firestore/Protos/nanopb/google/protobuf/any.pb.c
@@ -0,0 +1,36 @@
+/*
+ * Copyright 2018 Google
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/* Automatically generated nanopb constant definitions */
+/* Generated by nanopb-0.3.8 at Mon Feb 12 11:03:06 2018. */
+
+#include "any.pb.h"
+
+/* @@protoc_insertion_point(includes) */
+#if PB_PROTO_HEADER_VERSION != 30
+#error Regenerate this file with the current version of nanopb generator.
+#endif
+
+
+
+const pb_field_t google_protobuf_Any_fields[3] = {
+    PB_FIELD(  1, STRING  , SINGULAR, CALLBACK, FIRST, google_protobuf_Any, type_url, type_url, 0),
+    PB_FIELD(  2, BYTES   , SINGULAR, CALLBACK, OTHER, google_protobuf_Any, value, type_url, 0),
+    PB_LAST_FIELD
+};
+
+
+/* @@protoc_insertion_point(eof) */
diff --git a/Firestore/Protos/nanopb/google/protobuf/any.pb.h b/Firestore/Protos/nanopb/google/protobuf/any.pb.h
new file mode 100644
index 0000000..10a722e
--- /dev/null
+++ b/Firestore/Protos/nanopb/google/protobuf/any.pb.h
@@ -0,0 +1,69 @@
+/*
+ * Copyright 2018 Google
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/* Automatically generated nanopb header */
+/* Generated by nanopb-0.3.8 at Mon Feb 12 11:03:06 2018. */
+
+#ifndef PB_GOOGLE_PROTOBUF_ANY_PB_H_INCLUDED
+#define PB_GOOGLE_PROTOBUF_ANY_PB_H_INCLUDED
+#include <pb.h>
+
+/* @@protoc_insertion_point(includes) */
+#if PB_PROTO_HEADER_VERSION != 30
+#error Regenerate this file with the current version of nanopb generator.
+#endif
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* Struct definitions */
+typedef struct _google_protobuf_Any {
+    pb_callback_t type_url;
+    pb_callback_t value;
+/* @@protoc_insertion_point(struct:google_protobuf_Any) */
+} google_protobuf_Any;
+
+/* Default values for struct fields */
+
+/* Initializer values for message structs */
+#define google_protobuf_Any_init_default         {{{NULL}, NULL}, {{NULL}, NULL}}
+#define google_protobuf_Any_init_zero            {{{NULL}, NULL}, {{NULL}, NULL}}
+
+/* Field tags (for use in manual encoding/decoding) */
+#define google_protobuf_Any_type_url_tag         1
+#define google_protobuf_Any_value_tag            2
+
+/* Struct field encoding specification for nanopb */
+extern const pb_field_t google_protobuf_Any_fields[3];
+
+/* Maximum encoded size of messages (where known) */
+/* google_protobuf_Any_size depends on runtime parameters */
+
+/* Message IDs (where set with "msgid" option) */
+#ifdef PB_MSGID
+
+#define ANY_MESSAGES \
+
+
+#endif
+
+#ifdef __cplusplus
+} /* extern "C" */
+#endif
+/* @@protoc_insertion_point(eof) */
+
+#endif
diff --git a/Firestore/Protos/nanopb/google/protobuf/empty.pb.c b/Firestore/Protos/nanopb/google/protobuf/empty.pb.c
new file mode 100644
index 0000000..050af9c
--- /dev/null
+++ b/Firestore/Protos/nanopb/google/protobuf/empty.pb.c
@@ -0,0 +1,34 @@
+/*
+ * Copyright 2018 Google
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/* Automatically generated nanopb constant definitions */
+/* Generated by nanopb-0.3.8 at Mon Feb 12 11:03:06 2018. */
+
+#include "empty.pb.h"
+
+/* @@protoc_insertion_point(includes) */
+#if PB_PROTO_HEADER_VERSION != 30
+#error Regenerate this file with the current version of nanopb generator.
+#endif
+
+
+
+const pb_field_t google_protobuf_Empty_fields[1] = {
+    PB_LAST_FIELD
+};
+
+
+/* @@protoc_insertion_point(eof) */
diff --git a/Firestore/Protos/nanopb/google/protobuf/empty.pb.h b/Firestore/Protos/nanopb/google/protobuf/empty.pb.h
new file mode 100644
index 0000000..466e1fd
--- /dev/null
+++ b/Firestore/Protos/nanopb/google/protobuf/empty.pb.h
@@ -0,0 +1,66 @@
+/*
+ * Copyright 2018 Google
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/* Automatically generated nanopb header */
+/* Generated by nanopb-0.3.8 at Mon Feb 12 11:03:06 2018. */
+
+#ifndef PB_GOOGLE_PROTOBUF_EMPTY_PB_H_INCLUDED
+#define PB_GOOGLE_PROTOBUF_EMPTY_PB_H_INCLUDED
+#include <pb.h>
+
+/* @@protoc_insertion_point(includes) */
+#if PB_PROTO_HEADER_VERSION != 30
+#error Regenerate this file with the current version of nanopb generator.
+#endif
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* Struct definitions */
+typedef struct _google_protobuf_Empty {
+    char dummy_field;
+/* @@protoc_insertion_point(struct:google_protobuf_Empty) */
+} google_protobuf_Empty;
+
+/* Default values for struct fields */
+
+/* Initializer values for message structs */
+#define google_protobuf_Empty_init_default       {0}
+#define google_protobuf_Empty_init_zero          {0}
+
+/* Field tags (for use in manual encoding/decoding) */
+
+/* Struct field encoding specification for nanopb */
+extern const pb_field_t google_protobuf_Empty_fields[1];
+
+/* Maximum encoded size of messages (where known) */
+#define google_protobuf_Empty_size               0
+
+/* Message IDs (where set with "msgid" option) */
+#ifdef PB_MSGID
+
+#define EMPTY_MESSAGES \
+
+
+#endif
+
+#ifdef __cplusplus
+} /* extern "C" */
+#endif
+/* @@protoc_insertion_point(eof) */
+
+#endif
diff --git a/Firestore/Protos/nanopb/google/protobuf/wrappers.pb.c b/Firestore/Protos/nanopb/google/protobuf/wrappers.pb.c
new file mode 100644
index 0000000..41ab3c6
--- /dev/null
+++ b/Firestore/Protos/nanopb/google/protobuf/wrappers.pb.c
@@ -0,0 +1,81 @@
+/*
+ * Copyright 2018 Google
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/* Automatically generated nanopb constant definitions */
+/* Generated by nanopb-0.3.8 at Mon Feb 12 11:03:06 2018. */
+
+#include "wrappers.pb.h"
+
+/* @@protoc_insertion_point(includes) */
+#if PB_PROTO_HEADER_VERSION != 30
+#error Regenerate this file with the current version of nanopb generator.
+#endif
+
+
+
+const pb_field_t google_protobuf_DoubleValue_fields[2] = {
+    PB_FIELD(  1, DOUBLE  , SINGULAR, STATIC  , FIRST, google_protobuf_DoubleValue, value, value, 0),
+    PB_LAST_FIELD
+};
+
+const pb_field_t google_protobuf_FloatValue_fields[2] = {
+    PB_FIELD(  1, FLOAT   , SINGULAR, STATIC  , FIRST, google_protobuf_FloatValue, value, value, 0),
+    PB_LAST_FIELD
+};
+
+const pb_field_t google_protobuf_Int64Value_fields[2] = {
+    PB_FIELD(  1, INT64   , SINGULAR, STATIC  , FIRST, google_protobuf_Int64Value, value, value, 0),
+    PB_LAST_FIELD
+};
+
+const pb_field_t google_protobuf_UInt64Value_fields[2] = {
+    PB_FIELD(  1, UINT64  , SINGULAR, STATIC  , FIRST, google_protobuf_UInt64Value, value, value, 0),
+    PB_LAST_FIELD
+};
+
+const pb_field_t google_protobuf_Int32Value_fields[2] = {
+    PB_FIELD(  1, INT32   , SINGULAR, STATIC  , FIRST, google_protobuf_Int32Value, value, value, 0),
+    PB_LAST_FIELD
+};
+
+const pb_field_t google_protobuf_UInt32Value_fields[2] = {
+    PB_FIELD(  1, UINT32  , SINGULAR, STATIC  , FIRST, google_protobuf_UInt32Value, value, value, 0),
+    PB_LAST_FIELD
+};
+
+const pb_field_t google_protobuf_BoolValue_fields[2] = {
+    PB_FIELD(  1, BOOL    , SINGULAR, STATIC  , FIRST, google_protobuf_BoolValue, value, value, 0),
+    PB_LAST_FIELD
+};
+
+const pb_field_t google_protobuf_StringValue_fields[2] = {
+    PB_FIELD(  1, STRING  , SINGULAR, CALLBACK, FIRST, google_protobuf_StringValue, value, value, 0),
+    PB_LAST_FIELD
+};
+
+const pb_field_t google_protobuf_BytesValue_fields[2] = {
+    PB_FIELD(  1, BYTES   , SINGULAR, CALLBACK, FIRST, google_protobuf_BytesValue, value, value, 0),
+    PB_LAST_FIELD
+};
+
+
+/* On some platforms (such as AVR), double is really float.
+ * These are not directly supported by nanopb, but see example_avr_double.
+ * To get rid of this error, remove any double fields from your .proto.
+ */
+PB_STATIC_ASSERT(sizeof(double) == 8, DOUBLE_MUST_BE_8_BYTES)
+
+/* @@protoc_insertion_point(eof) */
diff --git a/Firestore/Protos/nanopb/google/protobuf/wrappers.pb.h b/Firestore/Protos/nanopb/google/protobuf/wrappers.pb.h
new file mode 100644
index 0000000..0e98785
--- /dev/null
+++ b/Firestore/Protos/nanopb/google/protobuf/wrappers.pb.h
@@ -0,0 +1,147 @@
+/*
+ * Copyright 2018 Google
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/* Automatically generated nanopb header */
+/* Generated by nanopb-0.3.8 at Mon Feb 12 11:03:06 2018. */
+
+#ifndef PB_GOOGLE_PROTOBUF_WRAPPERS_PB_H_INCLUDED
+#define PB_GOOGLE_PROTOBUF_WRAPPERS_PB_H_INCLUDED
+#include <pb.h>
+
+/* @@protoc_insertion_point(includes) */
+#if PB_PROTO_HEADER_VERSION != 30
+#error Regenerate this file with the current version of nanopb generator.
+#endif
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* Struct definitions */
+typedef struct _google_protobuf_BytesValue {
+    pb_callback_t value;
+/* @@protoc_insertion_point(struct:google_protobuf_BytesValue) */
+} google_protobuf_BytesValue;
+
+typedef struct _google_protobuf_StringValue {
+    pb_callback_t value;
+/* @@protoc_insertion_point(struct:google_protobuf_StringValue) */
+} google_protobuf_StringValue;
+
+typedef struct _google_protobuf_BoolValue {
+    bool value;
+/* @@protoc_insertion_point(struct:google_protobuf_BoolValue) */
+} google_protobuf_BoolValue;
+
+typedef struct _google_protobuf_DoubleValue {
+    double value;
+/* @@protoc_insertion_point(struct:google_protobuf_DoubleValue) */
+} google_protobuf_DoubleValue;
+
+typedef struct _google_protobuf_FloatValue {
+    float value;
+/* @@protoc_insertion_point(struct:google_protobuf_FloatValue) */
+} google_protobuf_FloatValue;
+
+typedef struct _google_protobuf_Int32Value {
+    int32_t value;
+/* @@protoc_insertion_point(struct:google_protobuf_Int32Value) */
+} google_protobuf_Int32Value;
+
+typedef struct _google_protobuf_Int64Value {
+    int64_t value;
+/* @@protoc_insertion_point(struct:google_protobuf_Int64Value) */
+} google_protobuf_Int64Value;
+
+typedef struct _google_protobuf_UInt32Value {
+    uint32_t value;
+/* @@protoc_insertion_point(struct:google_protobuf_UInt32Value) */
+} google_protobuf_UInt32Value;
+
+typedef struct _google_protobuf_UInt64Value {
+    uint64_t value;
+/* @@protoc_insertion_point(struct:google_protobuf_UInt64Value) */
+} google_protobuf_UInt64Value;
+
+/* Default values for struct fields */
+
+/* Initializer values for message structs */
+#define google_protobuf_DoubleValue_init_default {0}
+#define google_protobuf_FloatValue_init_default  {0}
+#define google_protobuf_Int64Value_init_default  {0}
+#define google_protobuf_UInt64Value_init_default {0}
+#define google_protobuf_Int32Value_init_default  {0}
+#define google_protobuf_UInt32Value_init_default {0}
+#define google_protobuf_BoolValue_init_default   {0}
+#define google_protobuf_StringValue_init_default {{{NULL}, NULL}}
+#define google_protobuf_BytesValue_init_default  {{{NULL}, NULL}}
+#define google_protobuf_DoubleValue_init_zero    {0}
+#define google_protobuf_FloatValue_init_zero     {0}
+#define google_protobuf_Int64Value_init_zero     {0}
+#define google_protobuf_UInt64Value_init_zero    {0}
+#define google_protobuf_Int32Value_init_zero     {0}
+#define google_protobuf_UInt32Value_init_zero    {0}
+#define google_protobuf_BoolValue_init_zero      {0}
+#define google_protobuf_StringValue_init_zero    {{{NULL}, NULL}}
+#define google_protobuf_BytesValue_init_zero     {{{NULL}, NULL}}
+
+/* Field tags (for use in manual encoding/decoding) */
+#define google_protobuf_BytesValue_value_tag     1
+#define google_protobuf_StringValue_value_tag    1
+#define google_protobuf_BoolValue_value_tag      1
+#define google_protobuf_DoubleValue_value_tag    1
+#define google_protobuf_FloatValue_value_tag     1
+#define google_protobuf_Int32Value_value_tag     1
+#define google_protobuf_Int64Value_value_tag     1
+#define google_protobuf_UInt32Value_value_tag    1
+#define google_protobuf_UInt64Value_value_tag    1
+
+/* Struct field encoding specification for nanopb */
+extern const pb_field_t google_protobuf_DoubleValue_fields[2];
+extern const pb_field_t google_protobuf_FloatValue_fields[2];
+extern const pb_field_t google_protobuf_Int64Value_fields[2];
+extern const pb_field_t google_protobuf_UInt64Value_fields[2];
+extern const pb_field_t google_protobuf_Int32Value_fields[2];
+extern const pb_field_t google_protobuf_UInt32Value_fields[2];
+extern const pb_field_t google_protobuf_BoolValue_fields[2];
+extern const pb_field_t google_protobuf_StringValue_fields[2];
+extern const pb_field_t google_protobuf_BytesValue_fields[2];
+
+/* Maximum encoded size of messages (where known) */
+#define google_protobuf_DoubleValue_size         9
+#define google_protobuf_FloatValue_size          5
+#define google_protobuf_Int64Value_size          11
+#define google_protobuf_UInt64Value_size         11
+#define google_protobuf_Int32Value_size          11
+#define google_protobuf_UInt32Value_size         6
+#define google_protobuf_BoolValue_size           2
+/* google_protobuf_StringValue_size depends on runtime parameters */
+/* google_protobuf_BytesValue_size depends on runtime parameters */
+
+/* Message IDs (where set with "msgid" option) */
+#ifdef PB_MSGID
+
+#define WRAPPERS_MESSAGES \
+
+
+#endif
+
+#ifdef __cplusplus
+} /* extern "C" */
+#endif
+/* @@protoc_insertion_point(eof) */
+
+#endif
diff --git a/Firestore/Protos/protos/google/protobuf/any.proto b/Firestore/Protos/protos/google/protobuf/any.proto
new file mode 100644
index 0000000..c748667
--- /dev/null
+++ b/Firestore/Protos/protos/google/protobuf/any.proto
@@ -0,0 +1,149 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// https://developers.google.com/protocol-buffers/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+syntax = "proto3";
+
+package google.protobuf;
+
+option csharp_namespace = "Google.Protobuf.WellKnownTypes";
+option go_package = "github.com/golang/protobuf/ptypes/any";
+option java_package = "com.google.protobuf";
+option java_outer_classname = "AnyProto";
+option java_multiple_files = true;
+option objc_class_prefix = "GPB";
+
+// `Any` contains an arbitrary serialized protocol buffer message along with a
+// URL that describes the type of the serialized message.
+//
+// Protobuf library provides support to pack/unpack Any values in the form
+// of utility functions or additional generated methods of the Any type.
+//
+// Example 1: Pack and unpack a message in C++.
+//
+//     Foo foo = ...;
+//     Any any;
+//     any.PackFrom(foo);
+//     ...
+//     if (any.UnpackTo(&foo)) {
+//       ...
+//     }
+//
+// Example 2: Pack and unpack a message in Java.
+//
+//     Foo foo = ...;
+//     Any any = Any.pack(foo);
+//     ...
+//     if (any.is(Foo.class)) {
+//       foo = any.unpack(Foo.class);
+//     }
+//
+//  Example 3: Pack and unpack a message in Python.
+//
+//     foo = Foo(...)
+//     any = Any()
+//     any.Pack(foo)
+//     ...
+//     if any.Is(Foo.DESCRIPTOR):
+//       any.Unpack(foo)
+//       ...
+//
+//  Example 4: Pack and unpack a message in Go
+//
+//      foo := &pb.Foo{...}
+//      any, err := ptypes.MarshalAny(foo)
+//      ...
+//      foo := &pb.Foo{}
+//      if err := ptypes.UnmarshalAny(any, foo); err != nil {
+//        ...
+//      }
+//
+// The pack methods provided by protobuf library will by default use
+// 'type.googleapis.com/full.type.name' as the type URL and the unpack
+// methods only use the fully qualified type name after the last '/'
+// in the type URL, for example "foo.bar.com/x/y.z" will yield type
+// name "y.z".
+//
+//
+// JSON
+// ====
+// The JSON representation of an `Any` value uses the regular
+// representation of the deserialized, embedded message, with an
+// additional field `@type` which contains the type URL. Example:
+//
+//     package google.profile;
+//     message Person {
+//       string first_name = 1;
+//       string last_name = 2;
+//     }
+//
+//     {
+//       "@type": "type.googleapis.com/google.profile.Person",
+//       "firstName": <string>,
+//       "lastName": <string>
+//     }
+//
+// If the embedded message type is well-known and has a custom JSON
+// representation, that representation will be embedded adding a field
+// `value` which holds the custom JSON in addition to the `@type`
+// field. Example (for message [google.protobuf.Duration][]):
+//
+//     {
+//       "@type": "type.googleapis.com/google.protobuf.Duration",
+//       "value": "1.212s"
+//     }
+//
+message Any {
+  // A URL/resource name whose content describes the type of the
+  // serialized protocol buffer message.
+  //
+  // For URLs which use the scheme `http`, `https`, or no scheme, the
+  // following restrictions and interpretations apply:
+  //
+  // * If no scheme is provided, `https` is assumed.
+  // * The last segment of the URL's path must represent the fully
+  //   qualified name of the type (as in `path/google.protobuf.Duration`).
+  //   The name should be in a canonical form (e.g., leading "." is
+  //   not accepted).
+  // * An HTTP GET on the URL must yield a [google.protobuf.Type][]
+  //   value in binary format, or produce an error.
+  // * Applications are allowed to cache lookup results based on the
+  //   URL, or have them precompiled into a binary to avoid any
+  //   lookup. Therefore, binary compatibility needs to be preserved
+  //   on changes to types. (Use versioned type names to manage
+  //   breaking changes.)
+  //
+  // Schemes other than `http`, `https` (or the empty scheme) might be
+  // used with implementation specific semantics.
+  //
+  string type_url = 1;
+
+  // Must be a valid serialized protocol buffer of the above specified type.
+  bytes value = 2;
+}
diff --git a/Firestore/Protos/protos/google/protobuf/empty.proto b/Firestore/Protos/protos/google/protobuf/empty.proto
new file mode 100644
index 0000000..03cacd2
--- /dev/null
+++ b/Firestore/Protos/protos/google/protobuf/empty.proto
@@ -0,0 +1,52 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// https://developers.google.com/protocol-buffers/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+syntax = "proto3";
+
+package google.protobuf;
+
+option csharp_namespace = "Google.Protobuf.WellKnownTypes";
+option go_package = "github.com/golang/protobuf/ptypes/empty";
+option java_package = "com.google.protobuf";
+option java_outer_classname = "EmptyProto";
+option java_multiple_files = true;
+option objc_class_prefix = "GPB";
+option cc_enable_arenas = true;
+
+// A generic empty message that you can re-use to avoid defining duplicated
+// empty messages in your APIs. A typical example is to use it as the request
+// or the response type of an API method. For instance:
+//
+//     service Foo {
+//       rpc Bar(google.protobuf.Empty) returns (google.protobuf.Empty);
+//     }
+//
+// The JSON representation for `Empty` is empty JSON object `{}`.
+message Empty {}
diff --git a/Firestore/Protos/protos/google/protobuf/wrappers.proto b/Firestore/Protos/protos/google/protobuf/wrappers.proto
new file mode 100644
index 0000000..0194763
--- /dev/null
+++ b/Firestore/Protos/protos/google/protobuf/wrappers.proto
@@ -0,0 +1,118 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// https://developers.google.com/protocol-buffers/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// Wrappers for primitive (non-message) types. These types are useful
+// for embedding primitives in the `google.protobuf.Any` type and for places
+// where we need to distinguish between the absence of a primitive
+// typed field and its default value.
+
+syntax = "proto3";
+
+package google.protobuf;
+
+option csharp_namespace = "Google.Protobuf.WellKnownTypes";
+option cc_enable_arenas = true;
+option go_package = "github.com/golang/protobuf/ptypes/wrappers";
+option java_package = "com.google.protobuf";
+option java_outer_classname = "WrappersProto";
+option java_multiple_files = true;
+option objc_class_prefix = "GPB";
+
+// Wrapper message for `double`.
+//
+// The JSON representation for `DoubleValue` is JSON number.
+message DoubleValue {
+  // The double value.
+  double value = 1;
+}
+
+// Wrapper message for `float`.
+//
+// The JSON representation for `FloatValue` is JSON number.
+message FloatValue {
+  // The float value.
+  float value = 1;
+}
+
+// Wrapper message for `int64`.
+//
+// The JSON representation for `Int64Value` is JSON string.
+message Int64Value {
+  // The int64 value.
+  int64 value = 1;
+}
+
+// Wrapper message for `uint64`.
+//
+// The JSON representation for `UInt64Value` is JSON string.
+message UInt64Value {
+  // The uint64 value.
+  uint64 value = 1;
+}
+
+// Wrapper message for `int32`.
+//
+// The JSON representation for `Int32Value` is JSON number.
+message Int32Value {
+  // The int32 value.
+  int32 value = 1;
+}
+
+// Wrapper message for `uint32`.
+//
+// The JSON representation for `UInt32Value` is JSON number.
+message UInt32Value {
+  // The uint32 value.
+  uint32 value = 1;
+}
+
+// Wrapper message for `bool`.
+//
+// The JSON representation for `BoolValue` is JSON `true` and `false`.
+message BoolValue {
+  // The bool value.
+  bool value = 1;
+}
+
+// Wrapper message for `string`.
+//
+// The JSON representation for `StringValue` is JSON string.
+message StringValue {
+  // The string value.
+  string value = 1;
+}
+
+// Wrapper message for `bytes`.
+//
+// The JSON representation for `BytesValue` is JSON string.
+message BytesValue {
+  // The bytes value.
+  bytes value = 1;
+}