Reland of Enable GN check for webrtc/base

webrtc/test/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.
 
 import("../webrtc.gni")
 import("//build/config/ui.gni")
@@ skipping 154 matching lines @@
 
   if (is_ios) {
     deps += [ "//webrtc/sdk:rtc_sdk_common_objc" ]
   }
 
   if (rtc_use_memcheck) {
     data = valgrind_webrtc_dependencies
   }
 }
 
+rtc_source_set("isolated_output") {
+  # This target was part of :test_support but it depends on //third_party/gflags
+  # and this can be a problem because test_support is pulled in from a target
+  # that is used by Chromium and they are not using gflags.
+  # Please do not merge this target with :test_support.
+  testonly = true
+  sources = [
+    "testsupport/isolated_output.cc",
+    "testsupport/isolated_output.h",
+  ]
+  deps = [
+    ":fileutils",
+    "../base:rtc_base_approved",
+    "//third_party/gflags",
+  ]
+}
+
 rtc_source_set("test_support") {
   testonly = true
 
   sources = [
     "gmock.h",
     "gtest.h",
-    "testsupport/isolated_output.cc",
-    "testsupport/isolated_output.h",
     "testsupport/packet_reader.cc",
     "testsupport/packet_reader.h",
     "testsupport/perf_test.cc",
     "testsupport/perf_test.h",
     "testsupport/trace_to_stderr.cc",
     "testsupport/trace_to_stderr.h",
     "testsupport/unittest_utils.h",
   ]
 
+  # Do not add a dependency on //third_party/gflags here because it breaks
+  # Chromium.
   deps = [
-    "../base:gtest_prod",
+    "..:webrtc_common",
     "../base:rtc_base_approved",
     "../common_video",
     "../system_wrappers",
     "//testing/gmock",
     "//testing/gtest",
-    "//third_party/gflags",
   ]
 
   public_deps = [
     ":fileutils",
   ]
 
   if (!build_with_chromium && is_clang) {
     # Suppress warnings from the Chromium Clang plugin (bugs.webrtc.org/163).
     suppressed_configs += [ "//build/config/clang:find_bad_constructs" ]
   }
@@ skipping 79 matching lines @@
     shard_timeout = 900
   }
 
   if (is_ios) {
     deps += [ ":test_support_unittests_bundle_data" ]
   }
 
   deps += [
     ":direct_transport",
     ":fileutils_unittests",
+    ":isolated_output",
     ":test_common",
     ":test_main",
     ":video_test_common",
     ":video_test_support",
     "../modules/video_capture",
     "//testing/gmock",
     "//testing/gtest",
     "//third_party/gflags",
   ]
 }
@@ skipping 181 matching lines @@
   ]
 }
 
 rtc_source_set("audio_codec_mocks") {
   testonly = true
   sources = [
     "mock_audio_decoder.h",
     "mock_audio_decoder_factory.h",
   ]
 }