Skip unit test if GYP_DEFINES="rtc_use_h264=1" is not set.

webrtc/media/media.gyp

 # Copyright (c) 2016 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.
 
 {
   'includes': [ '../build/common.gypi', ],
@@ skipping 273 matching lines @@
             '-Wno-sign-compare',
           ],
           'cflags_cc!': [
             '-Woverloaded-virtual',
           ],
           'msvs_disabled_warnings': [
             4245,  # conversion from 'int' to 'uint32_t', signed/unsigned mismatch.
             4389,  # signed/unsigned mismatch.
           ],
           'conditions': [
+            ['rtc_use_h264==1', {
+              'defines': [
+                 'WEBRTC_USE_H264'
+              ]
+            }],
             ['OS=="win"', {
               'msvs_settings': {
                 'VCLinkerTool': {
                   'AdditionalDependencies': [
                     # TODO(ronghuawu): Since we've included strmiids in
                     # libjingle_media target, we shouldn't need this here.
                     # Find out why it doesn't work without this.
                     'strmiids.lib',
                   ],
                 },
@@ skipping 50 matching lines @@
               'sources': [
                 'rtc_media_unittests.isolate',
               ],
             },
           ],
         }],
       ],  # conditions
     }],  # include_tests==1
   ],  # conditions
 }