Add the WebRTC.webkitApiCountPerSession metric.

content/content_tests.gypi

 # Copyright (c) 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.
 
 {
   'targets': [
     {
       'target_name': 'test_support_content',
       'type': 'static_library',
       'dependencies': [
@@ skipping 713 matching lines @@
             'renderer/media/rtc_video_decoder_unittest.cc',
             'renderer/media/video_source_handler_unittest.cc',
             'renderer/media/webrtc/media_stream_track_metrics_unittest.cc',
             'renderer/media/webrtc/webrtc_local_audio_track_adapter_unittest.cc',
             'renderer/media/webrtc/webrtc_video_capturer_adapter_unittest.cc',
             'renderer/media/webrtc_audio_capturer_unittest.cc',
             'renderer/media/webrtc_audio_renderer_unittest.cc',
             'renderer/media/webrtc_identity_service_unittest.cc',
             'renderer/media/webrtc_local_audio_source_provider_unittest.cc',
             'renderer/media/webrtc_local_audio_track_unittest.cc',
+            'renderer/media/webrtc_uma_histograms_unittest.cc',
           ],
           'dependencies': [
             '../third_party/libjingle/libjingle.gyp:libjingle_webrtc',
             '../third_party/libjingle/libjingle.gyp:libpeerconnection',
             '../third_party/webrtc/modules/modules.gyp:video_capture_module',
           ]
         }, {
           'sources!': [
             'renderer/media/media_stream_video_source_unittest.cc',
             'renderer/media/video_destination_handler_unittest.cc',
@@ skipping 1027 matching lines @@
                   'files': ['<(PRODUCT_DIR)/libnpapi_test_plugin.so'],
                 },
               ],
             }],
           ],
         },
       ],
     }],
   ],
 }