Added a kEchoCancellation constraint to turn off the audio processing. Also, change the the existing code not to use the libjingle interfaces. 

BUG=264611
TEST=content_unittests --getst_filter="*MediaStreamAudioProcessor*"

Review URL: https://codereview.chromium.org/227743004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@270728 0039d316-1c4b-4281-b951-d872f2087c98
21 files changed