Make it possible for tests to set up trace event handlers.

webrtc/BUILD.gn

 # Copyright (c) 2014 The WebRTC project authors. All Rights Reserved.
 #
 # Use of this source code is governed by a BSD-style license
 # that can be found in the LICENSE file in the root of the source
 # tree. An additional intellectual property rights grant can be found
 # in the file PATENTS.  All contributing project authors may
 # be found in the AUTHORS file in the root of the source tree.
 
 # TODO(kjellander): Rebase this to webrtc/build/common.gypi changes after r6330.
 
 import("//build/config/linux/pkg_config.gni")
 import("//build/config/sanitizers/sanitizers.gni")
 import("webrtc.gni")
 import("//third_party/protobuf/proto_library.gni")
 if (is_android) {
   import("//build/config/android/config.gni")
   import("//build/config/android/rules.gni")
 }
 
 # Contains the defines and includes in common.gypi that are duplicated both as
 # target_defaults and direct_dependent_settings.
 config("common_inherited_config") {
   defines = []
   cflags = []
   ldflags = []
   if (build_with_mozilla) {
     defines += [ "WEBRTC_MOZILLA_BUILD" ]
   }
+  if (rtc_include_tests) {
+    defines += [ "WEBRTC_NON_CONST_TRACE_EVENT_HANDLERS" ]

[kjellander_webrtc, 2017/08/16 12:17:14]

Please add a comment explaining why this is needed and what effect it has.

[kwiberg-webrtc, 2017/08/16 13:11:40]

Please consider always defining this (to 0 or 1, for off/on), and testing it
with #if instead of #ifdef. See
https://groups.google.com/d/msg/discuss-webrtc/tz0Qre1j2QU/iMTSv2lQCAAJ

[ehmaldonado_webrtc, 2017/08/16 13:40:57]

Done.

+  }
   if (build_with_chromium) {
     defines = [
       # TODO(kjellander): Cleanup unused ones and move defines closer to
       # the source when webrtc:4256 is completed.
       "FEATURE_ENABLE_VOICEMAIL",
       "EXPAT_RELATIVE_PATH",
       "GTEST_RELATIVE_PATH",
       "WEBRTC_CHROMIUM_BUILD",
     ]
     include_dirs = [
@@ skipping 495 matching lines @@
       ]
 
       deps = [
         "examples:AppRTCMobile_javalib",
         "sdk/android:libjingle_peerconnection_java",
         "//base:base_java_test_support",
       ]
     }
   }
 }