Fix compilation if HAVE_WEBRTC_VIDEO is not defined.

talk/libjingle_tests.gyp

 #
 # libjingle
 # Copyright 2012 Google Inc.
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are met:
 #
 #  1. Redistributions of source code must retain the above copyright notice,
 #     this list of conditions and the following disclaimer.
 #  2. Redistributions in binary form must reproduce the above copyright notice,
@@ skipping 78 matching lines @@
         'media/base/testutils.h',
         'media/base/turnutils_unittest.cc',
         'media/base/videoadapter_unittest.cc',
         'media/base/videocapturer_unittest.cc',
         'media/base/videocommon_unittest.cc',
         'media/base/videoengine_unittest.h',
         'media/base/videoframe_unittest.h',
         'media/devices/dummydevicemanager_unittest.cc',
         'media/devices/filevideocapturer_unittest.cc',
         'media/sctp/sctpdataengine_unittest.cc',
+        'media/webrtc/nullwebrtcvideoengine_unittest.cc',
         'media/webrtc/simulcast_unittest.cc',
         'media/webrtc/webrtcmediaengine_unittest.cc',
         'media/webrtc/webrtcvideocapturer_unittest.cc',
         'media/webrtc/webrtcvideoframe_unittest.cc',
         'media/webrtc/webrtcvideoframefactory_unittest.cc',
         # Disabled because some tests fail.
         # TODO(ronghuawu): Reenable these tests.
         # 'media/devices/devicemanager_unittest.cc',
         'media/webrtc/webrtcvideoengine2_unittest.cc',
         'media/webrtc/webrtcvoiceengine_unittest.cc',
@@ skipping 352 matching lines @@
             'build/isolate.gypi',
           ],
           'sources': [
             'peerconnection_unittests.isolate',
           ],
         },
       ],
     }],
   ],
 }