Remove use_system_ffmpeg-related logic from media and other mainline gyp files.

media/media.gyp

 # Copyright (c) 2012 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.
 
 {
   'variables': {
     'chromium_code': 1,
     # Override to dynamically link the cras (ChromeOS audio) library.
     'use_cras%': 0,
     # Option e.g. for Linux distributions to link pulseaudio directly
@@ skipping 491 matching lines @@
             'defines': [
               'MEDIA_DISABLE_LIBVPX',
             ],
           },
           # Exclude the sources that depend on libvpx.
           'sources!': [
             'filters/vpx_video_decoder.cc',
             'filters/vpx_video_decoder.h',
           ],
         }],
-        ['use_system_ffmpeg == 1', {
-          'cflags': [
-            '<!(python <(DEPTH)/tools/compile_test/compile_test.py '
-                '--code "#define __STDC_CONSTANT_MACROS\n'
-                '#include <libavcodec/avcodec.h>\n'
-                'int test() { return AV_CODEC_ID_OPUS; }" '
-                '--on-failure -DCHROMIUM_OMIT_AV_CODEC_ID_OPUS=1)',
-
-            '<!(python <(DEPTH)/tools/compile_test/compile_test.py '
-                '--code "#define __STDC_CONSTANT_MACROS\n'
-                '#include <libavcodec/avcodec.h>\n'
-                'int test() { return AV_CODEC_ID_VP9; }" '
-                '--on-failure -DCHROMIUM_OMIT_AV_CODEC_ID_VP9=1)',
-
-            '<!(python <(DEPTH)/tools/compile_test/compile_test.py '
-                '--code "#define __STDC_CONSTANT_MACROS\n'
-                '#include <libavcodec/avcodec.h>\n'
-                'int test() { struct AVFrame frame;\n'
-                'return av_frame_get_channels(&frame); }" '
-                '--on-failure -DCHROMIUM_NO_AVFRAME_CHANNELS=1)',
-          ],
-        }],
         ['OS == "ios"', {
           'includes': [
             # For shared_memory_support_sources variable.
             'shared_memory_support.gypi',
           ],
           'sources': [
             'base/media_stub.cc',
             # These sources are normally built via a dependency on the
             # shared_memory_support target, but that target is not built on iOS.
             # Instead, directly build only the files that are needed for iOS.
@@ skipping 1179 matching lines @@
           ],
           'sources': [
             'base/simd/sinc_resampler_sse.cc',
             'base/simd/vector_math_sse.cc',
           ],
         }, # end of target media_sse
       ],
     }],
   ],
 }