Replace WebAudio MediaCodec usage with FFmpeg. A ~4x improvement.

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 1805 matching lines @@
           'target_name': 'media_android_jni_headers',
           'type': 'none',
           'sources': [
             'base/android/java/src/org/chromium/media/AudioManagerAndroid.java',
             'base/android/java/src/org/chromium/media/AudioRecordInput.java',
             'base/android/java/src/org/chromium/media/MediaCodecBridge.java',
             'base/android/java/src/org/chromium/media/MediaCodecUtil.java',
             'base/android/java/src/org/chromium/media/MediaDrmBridge.java',
             'base/android/java/src/org/chromium/media/MediaPlayerBridge.java',
             'base/android/java/src/org/chromium/media/MediaPlayerListener.java',
-            'base/android/java/src/org/chromium/media/WebAudioMediaCodecBridge.java',
           ],
           'variables': {
             'jni_gen_package': 'media',
           },
           'includes': ['../build/jni_generator.gypi'],
         },
         {
           # GN: //media/base/android:video_capture_android_jni_headers
           'target_name': 'video_capture_android_jni_headers',
           'type': 'none',
@@ skipping 57 matching lines @@
             'base/android/media_statistics.cc',
             'base/android/media_statistics.h',
             'base/android/media_task_runner.cc',
             'base/android/media_task_runner.h',
             'base/android/media_url_interceptor.h',
             'base/android/provision_fetcher.h',
             'base/android/sdk_media_codec_bridge.cc',
             'base/android/sdk_media_codec_bridge.h',
             'base/android/video_decoder_job.cc',
             'base/android/video_decoder_job.h',
-            'base/android/webaudio_media_codec_bridge.cc',
-            'base/android/webaudio_media_codec_bridge.h',
-            'base/android/webaudio_media_codec_info.h',
           ],
           'conditions': [
             # Only 64 bit builds are using android-21 NDK library, check common.gypi
             ['target_arch=="arm64" or target_arch=="x64" or target_arch=="mips64el"', {
               'sources': [
                 'base/android/ndk_media_codec_bridge.cc',
                 'base/android/ndk_media_codec_bridge.h',
                 'base/android/ndk_media_codec_wrapper.cc',
               ],
             }],
@@ skipping 225 matching lines @@
               'dependencies': [
                 '../tools/xdisplaycheck/xdisplaycheck.gyp:xdisplaycheck',
               ],
             }],
           ],
         },
       ],
     }],
   ],
 }