tracing v2: Introduce TraceBufferWriter

components/tracing.gyp

 # Copyright (c) 2012 The Chromium Authors. All rights reserved.
 #
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 # This file is intentionally a gyp file rather than a gypi for dependencies
 # reasons. The other gypi files include content.gyp and content_common depends
 # on this, thus if you try to rename this to gypi and include it in
 # components.gyp, you will get a circular dependency error.
 {
@@ skipping 31 matching lines @@
         'tracing/common/tracing_messages.h',
         'tracing/common/tracing_switches.cc',
         'tracing/common/tracing_switches.h',
         'tracing/core/proto_utils.h',
         'tracing/core/proto_zero_message.cc',
         'tracing/core/proto_zero_message.h',
         'tracing/core/proto_zero_message_handle.cc',
         'tracing/core/proto_zero_message_handle.h',
         'tracing/core/scattered_stream_writer.cc',
         'tracing/core/scattered_stream_writer.h',
+        'tracing/core/trace_buffer_writer.cc',
+        'tracing/core/trace_buffer_writer.h',
         'tracing/core/trace_ring_buffer.cc',
         'tracing/core/trace_ring_buffer.h',
         'tracing/tracing_export.h',
       ],
       'target_conditions': [
         ['>(nacl_untrusted_build)==1', {
           'sources!': [
             'tracing/common/process_metrics_memory_dump_provider.cc',
           ],
         }],
@@ skipping 28 matching lines @@
         'generate_python': 0,
       },
       'sources': [
         'tracing/test/example_messages.proto',
       ],
       'dependencies': [
         'proto_zero_plugin#host',
       ],
       'includes': ['../build/protoc.gypi'],
     },
+    {
+      # Official protobuf used by tests to verify that the Tracing V2 output is
+      # effectively proto-compatible.
+      # GN version: //components/tracing:golden_protos_for_tests
+      'target_name': 'golden_protos_for_tests',
+      'type': 'static_library',
+      'variables': {
+        'proto_in_dir': 'tracing/proto',
+        'proto_out_dir': 'components/tracing/test/golden_protos',
+      },
+      'sources': [
+        'tracing/proto/events_chunk.proto',
+      ],
+      'includes': ['../build/protoc.gypi'],
+    },
   ],
 }