Integrate changes from internal code.

protoc
* Enum values may now have custom options, using syntax similar to field
  options.
* Fixed bug where .proto files which use custom options but don't actually
  define them (i.e. they import another .proto file defining the options)
  had to explicitly import descriptor.proto.
* Adjacent string literals in .proto files will now be concatenated, like in
  C.

C++
* Generated message classes now have a Swap() method which efficiently swaps
  the contents of two objects.
* All message classes now have a SpaceUsed() method which returns an estimate
  of the number of bytes of allocated memory currently owned by the object.
  This is particularly useful when you are reusing a single message object
  to improve performance but want to make sure it doesn't bloat up too large.
* New method Message::SerializeAsString() returns a string containing the
  serialized data.  May be more convenient than calling
  SerializeToString(string*).
* In debug mode, log error messages when string-type fields are found to
  contain bytes that are not valid UTF-8.
* Fixed bug where a message with multiple extension ranges couldn't parse
  extensions.
* Fixed bug where MergeFrom(const Message&) didn't do anything if invoked on
  a message that contained no fields (but possibly contained extensions).
* Fixed ShortDebugString() to not be O(n^2).  Durr.
* Fixed crash in TextFormat parsing if the first token in the input caused a
  tokenization error.

Java
* New overload of mergeFrom() which parses a slice of a byte array instead
  of the whole thing.
* New method ByteString.asReadOnlyByteBuffer() does what it sounds like.
* Improved performance of isInitialized() when optimizing for code size.

Python
* Corrected ListFields() signature in Message base class to match what
  subclasses actually implement.
* Some minor refactoring.

1 files changed, 11 insertions, 2 deletions

diff --git a/src/google/protobuf/wire_format.cc b/src/google/protobuf/wire_format.cc
index 219d1f27..99ea619b 100644
--- a/src/google/protobuf/wire_format.cc
+++ b/src/google/protobuf/wire_format.cc
@@ -648,8 +648,7 @@ bool WireFormat::SerializeFieldWithCachedSizes(
 
       // Handle strings separately so that we can get string references
       // instead of copying.
-      case FieldDescriptor::TYPE_STRING:
-      case FieldDescriptor::TYPE_BYTES: {
+      case FieldDescriptor::TYPE_STRING: {
           string scratch;
           const string& value = field->is_repeated() ?
             message_reflection->GetRepeatedStringReference(
@@ -658,6 +657,16 @@ bool WireFormat::SerializeFieldWithCachedSizes(
           if (!WriteString(field->number(), value, output)) return false;
         break;
       }
+
+      case FieldDescriptor::TYPE_BYTES: {
+          string scratch;
+          const string& value = field->is_repeated() ?
+            message_reflection->GetRepeatedStringReference(
+              message, field, j, &scratch) :
+            message_reflection->GetStringReference(message, field, &scratch);
+          if (!WriteBytes(field->number(), value, output)) return false;
+        break;
+      }
     }
   }