GitLab

Loopback audio capture will be used for desktop capture API, to
capture system audio so it can be included in screencast streams.

BUG=223639

Review URL: https://chromiumcodereview.appspot.com/23848005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@223569 0039d316-1c4b-4281-b951-d872f2087c98