Add an unbundled ffmpeg.gyp file.

build/linux/unbundle/replace_gyp_files.py

 #!/usr/bin/env python
 # 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.
 
 """
 Replaces gyp files in tree with files from here that
 make the build use system libraries.
 """
 
 
 import os.path
 import shutil
 import sys
 
 
 REPLACEMENTS = {
   'use_system_bzip2': 'third_party/bzip2/bzip2.gyp',
   'use_system_expat': 'third_party/expat/expat.gyp',
+  'use_system_ffmpeg': 'third_party/ffmpeg/ffmpeg.gyp',
   'use_system_flac': 'third_party/flac/flac.gyp',
   'use_system_harfbuzz': 'third_party/harfbuzz-ng/harfbuzz.gyp',
   'use_system_icu': 'third_party/icu/icu.gyp',
   'use_system_jsoncpp': 'third_party/jsoncpp/jsoncpp.gyp',
   'use_system_libevent': 'third_party/libevent/libevent.gyp',
   'use_system_libjpeg': 'third_party/libjpeg/libjpeg.gyp',
   'use_system_libpng': 'third_party/libpng/libpng.gyp',
   'use_system_libusb': 'third_party/libusb/libusb.gyp',
   'use_system_libvpx': 'third_party/libvpx/libvpx.gyp',
   'use_system_libwebp': 'third_party/libwebp/libwebp.gyp',
@@ skipping 22 matching lines @@
 
     # Copy the gyp file from directory of this script to target path.
     shutil.copyfile(os.path.join(my_dirname, os.path.basename(path)),
                     os.path.join(source_tree_root, path))
 
   return 0
 
 
 if __name__ == '__main__':
   sys.exit(DoMain(sys.argv))