Add GYP flag to optionally enable the Hangout Services extension in

chrome/browser/extensions/api/webrtc_audio_private/webrtc_audio_private_browsertest.cc

 // Copyright 2013 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.
 
 #include "base/json/json_writer.h"
 #include "base/strings/string_util.h"
 #include "base/strings/stringprintf.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/synchronization/waitable_event.h"
 #include "base/threading/platform_thread.h"
@@ skipping 356 matching lines @@
 
 class HangoutServicesBrowserTest : public AudioWaitingExtensionTest {
  public:
   virtual void SetUp() OVERRIDE {
     // Make sure the Hangout Services component extension gets loaded.
     ComponentLoader::EnableBackgroundExtensionsForTesting();
     AudioWaitingExtensionTest::SetUp();
   }
 };
 
-#if defined(GOOGLE_CHROME_BUILD)
+#if defined(GOOGLE_CHROME_BUILD) || defined(ENABLE_HANGOUT_SERVICES_EXTENSION)
 IN_PROC_BROWSER_TEST_F(HangoutServicesBrowserTest,
                        RunComponentExtensionTest) {
   // This runs the end-to-end JavaScript test for the Hangout Services
   // component extension, which uses the webrtcAudioPrivate API among
   // others.
   ASSERT_TRUE(StartEmbeddedTestServer());
   GURL url(embedded_test_server()->GetURL(
                "/extensions/hangout_services_test.html"));
   // The "externally connectable" extension permission doesn't seem to
   // like when we use 127.0.0.1 as the host, but using localhost works.
@@ skipping 12 matching lines @@
   g_browser_process->webrtc_log_uploader()->
       OverrideUploadWithBufferForTesting(&dummy);
 
   ASSERT_TRUE(content::ExecuteScript(tab, "browsertestRunAllTests();"));
 
   content::TitleWatcher title_watcher(tab, base::ASCIIToUTF16("success"));
   title_watcher.AlsoWaitForTitle(base::ASCIIToUTF16("failure"));
   base::string16 result = title_watcher.WaitAndGetTitle();
   EXPECT_EQ(base::ASCIIToUTF16("success"), result);
 }
-#endif  // defined(GOOGLE_CHROME_BUILD)
+#endif  // defined(GOOGLE_CHROME_BUILD) || defined(ENABLE_HANGOUT_SERVICES_EXTENSION)
 
 }  // namespace extensions