Export of internal Abseil changes.

--
c321829735accc2e6beb81e6a5a4421e5647b876 by CJ Johnson <johnsoncj@google.com>:

Updates the definition of InlinedVector::swap(InlinedVector&) to be exception safe and adds exception safety tests

PiperOrigin-RevId: 255511536

--
0d86445891748efb09430eb9ede267b54185a246 by CJ Johnson <johnsoncj@google.com>:

Updates the definition of InlinedVector::erase(...) to be exception safe and adds an exception safety test for it.

PiperOrigin-RevId: 255492671

--
f07e8fa62dfe9eb0d025b27fca8c6db43c5a328f by CJ Johnson <johnsoncj@google.com>:

Updates the implementation of InlinedVector::emplace_back(...) to be exception safe and adds exception safety tests

PiperOrigin-RevId: 255422837

--
4c3be92bfe4c1636a03cef8fd5aa802fed0d2c61 by Abseil Team <absl-team@google.com>:

Internal Change

PiperOrigin-RevId: 255422693

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6df38ea42f00678c357a539016163f8ac4c084e6 by Gennadiy Rozental <rogeeff@google.com>:

Introduce public interfaces for setting and getting program usage messages.

PiperOrigin-RevId: 255291467

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8f21d594aed3971d37db70226847c693eb548edb by Laramie Leavitt <lar@google.com>:

Move absl/random's copy of ABSL_ATTRIBUTE_FORCE_INLINE and
ABSL_ATTRIBUTE_NEVER_INLINE into .cc files and rename to
prevent conflicts.

https://github.com/abseil/abseil-cpp/issues/343

PiperOrigin-RevId: 255288599

--
6b7430ad0c8bd860fb9394894f5eeedd1acc9f77 by CJ Johnson <johnsoncj@google.com>:

Updates the ScopedAllocatorWorks test for InlinedVector to not rely on the byte count allocated by the standard library

In doing so, removes LegacyNextCapacityFrom(...) impl function from InlinedVector

Also applies clang-format to the test file

PiperOrigin-RevId: 255207606
GitOrigin-RevId: c321829735accc2e6beb81e6a5a4421e5647b876
Change-Id: I7438211c36c4549fca2e866658f8d579c65d7d52

7 files changed, 110 insertions, 51 deletions

diff --git a/absl/flags/BUILD.bazel b/absl/flags/BUILD.bazel
index bb1a7aac..82e6ffcf 100644
--- a/absl/flags/BUILD.bazel
+++ b/absl/flags/BUILD.bazel
@@ -158,9 +158,11 @@ cc_library(
     name = "usage",
     srcs = [
         "internal/usage.cc",
+        "usage.cc",
     ],
     hdrs = [
         "internal/usage.h",
+        "usage.h",
     ],
     copts = ABSL_DEFAULT_COPTS,
     linkopts = ABSL_DEFAULT_LINKOPTS,
diff --git a/absl/flags/CMakeLists.txt b/absl/flags/CMakeLists.txt
index 9e0b441b..9c936ecc 100644
--- a/absl/flags/CMakeLists.txt
+++ b/absl/flags/CMakeLists.txt
@@ -144,8 +144,10 @@ absl_cc_library(
     flags_usage
   SRCS
     "internal/usage.cc"
+    "usage.cc"
   HDRS
     "internal/usage.h"
+    "usage.h"
   COPTS
     ${ABSL_DEFAULT_COPTS}
   LINKOPTS
diff --git a/absl/flags/internal/usage.cc b/absl/flags/internal/usage.cc
index f17cc6c5..b1ff8b83 100644
--- a/absl/flags/internal/usage.cc
+++ b/absl/flags/internal/usage.cc
@@ -21,6 +21,7 @@
 #include "absl/flags/flag.h"
 #include "absl/flags/internal/path_util.h"
 #include "absl/flags/internal/program_name.h"
+#include "absl/flags/usage.h"
 #include "absl/flags/usage_config.h"
 #include "absl/strings/ascii.h"
 #include "absl/strings/str_cat.h"
@@ -204,7 +205,7 @@ void FlagsHelpImpl(std::ostream& out, flags_internal::FlagKindFilter filter_cb,
                    HelpFormat format = HelpFormat::kHumanReadable) {
   if (format == HelpFormat::kHumanReadable) {
     out << flags_internal::ShortProgramInvocationName() << ": "
-        << flags_internal::ProgramUsageMessage() << "\n\n";
+        << absl::ProgramUsageMessage() << "\n\n";
   } else {
     // XML schema is not a part of our public API for now.
     out << "<?xml version=\"1.0\"?>\n"
@@ -213,7 +214,7 @@ void FlagsHelpImpl(std::ostream& out, flags_internal::FlagKindFilter filter_cb,
         // The program name and usage.
         << XMLElement("program", flags_internal::ShortProgramInvocationName())
         << '\n'
-        << XMLElement("usage", flags_internal::ProgramUsageMessage()) << '\n';
+        << XMLElement("usage", absl::ProgramUsageMessage()) << '\n';
   }
 
   // Map of package name to
@@ -278,39 +279,9 @@ void FlagsHelpImpl(std::ostream& out, flags_internal::FlagKindFilter filter_cb,
   }
 }
 
-ABSL_CONST_INIT absl::Mutex usage_message_guard(absl::kConstInit);
-ABSL_CONST_INIT std::string* program_usage_message
-    GUARDED_BY(usage_message_guard) = nullptr;
-
 }  // namespace
 
 // --------------------------------------------------------------------
-// Sets the "usage" message to be used by help reporting routines.
-
-void SetProgramUsageMessage(absl::string_view new_usage_message) {
-  absl::MutexLock l(&usage_message_guard);
-
-  if (flags_internal::program_usage_message != nullptr) {
-    ABSL_INTERNAL_LOG(FATAL, "SetProgramUsageMessage() called twice.");
-    std::exit(1);
-  }
-
-  program_usage_message = new std::string(new_usage_message);
-}
-
-// --------------------------------------------------------------------
-// Returns the usage message set by SetProgramUsageMessage().
-// Note: We able to return string_view here only because calling
-// SetProgramUsageMessage twice is prohibited.
-absl::string_view ProgramUsageMessage() {
-  absl::MutexLock l(&usage_message_guard);
-
-  return program_usage_message != nullptr
-             ? absl::string_view(*program_usage_message)
-             : "Warning: SetProgramUsageMessage() never called";
-}
-
-// --------------------------------------------------------------------
 // Produces the help message describing specific flag.
 void FlagHelp(std::ostream& out, const flags_internal::CommandLineFlag& flag,
               HelpFormat format) {
diff --git a/absl/flags/internal/usage.h b/absl/flags/internal/usage.h
index 2d0ea7a7..33f3f969 100644
--- a/absl/flags/internal/usage.h
+++ b/absl/flags/internal/usage.h
@@ -29,20 +29,6 @@
 namespace absl {
 namespace flags_internal {
 
-// Sets the "usage" message to be used by help reporting routines.
-// For example:
-//  absl::SetProgramUsageMessage(
-//      absl::StrCat("This program does nothing.  Sample usage:\n", argv[0],
-//                   " <uselessarg1> <uselessarg2>"));
-// Do not include commandline flags in the usage: we do that for you!
-// Note: Calling SetProgramUsageMessage twice will trigger a call to std::exit.
-void SetProgramUsageMessage(absl::string_view new_usage_message);
-
-// Returns the usage message set by SetProgramUsageMessage().
-absl::string_view ProgramUsageMessage();
-
-// --------------------------------------------------------------------
-
 // The format to report the help messages in.
 enum class HelpFormat {
   kHumanReadable,
diff --git a/absl/flags/internal/usage_test.cc b/absl/flags/internal/usage_test.cc
index cb40aa42..fa121fc9 100644
--- a/absl/flags/internal/usage_test.cc
+++ b/absl/flags/internal/usage_test.cc
@@ -13,14 +13,16 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+#include "absl/flags/internal/usage.h"
+
 #include <sstream>
 
 #include "gtest/gtest.h"
 #include "absl/flags/flag.h"
-#include "absl/flags/parse.h"
 #include "absl/flags/internal/path_util.h"
 #include "absl/flags/internal/program_name.h"
-#include "absl/flags/internal/usage.h"
+#include "absl/flags/parse.h"
+#include "absl/flags/usage.h"
 #include "absl/flags/usage_config.h"
 #include "absl/memory/memory.h"
 #include "absl/strings/match.h"
@@ -81,11 +83,11 @@ class UsageReportingTest : public testing::Test {
 using UsageReportingDeathTest = UsageReportingTest;
 
 TEST_F(UsageReportingDeathTest, TestSetProgramUsageMessage) {
-  EXPECT_EQ(flags::ProgramUsageMessage(), "Custom usage message");
+  EXPECT_EQ(absl::ProgramUsageMessage(), "Custom usage message");
 
 #ifndef _WIN32
   // TODO(rogeeff): figure out why this does not work on Windows.
-  EXPECT_DEATH(flags::SetProgramUsageMessage("custom usage message"),
+  EXPECT_DEATH(absl::SetProgramUsageMessage("custom usage message"),
                ".*SetProgramUsageMessage\\(\\) called twice.*");
 #endif
 }
@@ -360,7 +362,7 @@ TEST_F(UsageReportingTest, TestUsageFlag_helpon) {
 int main(int argc, char* argv[]) {
   absl::GetFlag(FLAGS_undefok);  // Force linking of parse.cc
   flags::SetProgramInvocationName("usage_test");
-  flags::SetProgramUsageMessage("Custom usage message");
+  absl::SetProgramUsageMessage("Custom usage message");
   ::testing::InitGoogleTest(&argc, argv);
 
   return RUN_ALL_TESTS();
diff --git a/absl/flags/usage.cc b/absl/flags/usage.cc
new file mode 100644
index 00000000..4c01f510
--- /dev/null
+++ b/absl/flags/usage.cc
@@ -0,0 +1,56 @@
+//
+// Copyright 2019 The Abseil Authors.
+//
+// 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
+//
+//      https://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.
+#include "absl/flags/usage.h"
+
+#include <string>
+
+#include "absl/flags/internal/usage.h"
+#include "absl/synchronization/mutex.h"
+
+namespace absl {
+namespace flags_internal {
+namespace {
+ABSL_CONST_INIT absl::Mutex usage_message_guard(absl::kConstInit);
+ABSL_CONST_INIT std::string* program_usage_message
+    GUARDED_BY(usage_message_guard) = nullptr;
+}  // namespace
+}  // namespace flags_internal
+
+// --------------------------------------------------------------------
+// Sets the "usage" message to be used by help reporting routines.
+void SetProgramUsageMessage(absl::string_view new_usage_message) {
+  absl::MutexLock l(&flags_internal::usage_message_guard);
+
+  if (flags_internal::program_usage_message != nullptr) {
+    ABSL_INTERNAL_LOG(FATAL, "SetProgramUsageMessage() called twice.");
+    std::exit(1);
+  }
+
+  flags_internal::program_usage_message = new std::string(new_usage_message);
+}
+
+// --------------------------------------------------------------------
+// Returns the usage message set by SetProgramUsageMessage().
+// Note: We able to return string_view here only because calling
+// SetProgramUsageMessage twice is prohibited.
+absl::string_view ProgramUsageMessage() {
+  absl::MutexLock l(&flags_internal::usage_message_guard);
+
+  return flags_internal::program_usage_message != nullptr
+             ? absl::string_view(*flags_internal::program_usage_message)
+             : "Warning: SetProgramUsageMessage() never called";
+}
+
+}  // namespace absl
diff --git a/absl/flags/usage.h b/absl/flags/usage.h
new file mode 100644
index 00000000..3a121071
--- /dev/null
+++ b/absl/flags/usage.h
@@ -0,0 +1,40 @@
+//
+//  Copyright 2019 The Abseil Authors.
+//
+// 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
+//
+//      https://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.
+
+#ifndef ABSL_FLAGS_USAGE_H_
+#define ABSL_FLAGS_USAGE_H_
+
+#include "absl/strings/string_view.h"
+
+// --------------------------------------------------------------------
+// Usage reporting interfaces
+
+namespace absl {
+
+// Sets the "usage" message to be used by help reporting routines.
+// For example:
+//  absl::SetProgramUsageMessage(
+//      absl::StrCat("This program does nothing.  Sample usage:\n", argv[0],
+//                   " <uselessarg1> <uselessarg2>"));
+// Do not include commandline flags in the usage: we do that for you!
+// Note: Calling SetProgramUsageMessage twice will trigger a call to std::exit.
+void SetProgramUsageMessage(absl::string_view new_usage_message);
+
+// Returns the usage message set by SetProgramUsageMessage().
+absl::string_view ProgramUsageMessage();
+
+}  // namespace absl
+
+#endif  // ABSL_FLAGS_USAGE_H_