The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/1b679d7ce7918dd41e68e1170c7f6dfd4edcc4bd

commit 1b679d7ce7918dd41e68e1170c7f6dfd4edcc4bd
Author: hongchan <hongchan@chromium.org>
Date: Wed Dec 21 16:38:16 2016

Remove input/source components from AudioDestination

Based on the comment in the code and the investigation around it, we do
not use sourceData meaningfully in the code. Considering the live input
is done by gUM, we can safely remove this from the render call chain.

This is the first part of refactoring/clean up of AudioDestination to
support the new threading model of AudioWorkletNode.

BUG= 675988 
TEST=

Review-Url: https://codereview.chromium.org/2590983003
Cr-Commit-Position: refs/heads/master@{#440126}

[modify] https://crrev.com/1b679d7ce7918dd41e68e1170c7f6dfd4edcc4bd/content/renderer/media/renderer_webaudiodevice_impl.cc
[modify] https://crrev.com/1b679d7ce7918dd41e68e1170c7f6dfd4edcc4bd/third_party/WebKit/Source/platform/audio/AudioDestination.cpp
[modify] https://crrev.com/1b679d7ce7918dd41e68e1170c7f6dfd4edcc4bd/third_party/WebKit/Source/platform/audio/AudioDestination.h
[modify] https://crrev.com/1b679d7ce7918dd41e68e1170c7f6dfd4edcc4bd/third_party/WebKit/Source/platform/exported/WebAudioDevice.cpp
[modify] https://crrev.com/1b679d7ce7918dd41e68e1170c7f6dfd4edcc4bd/third_party/WebKit/public/platform/WebAudioDevice.h