This CL is part of the code in https://codereview.chromium.org/11316275/ to refactor the media UI.

      This patch does
# split CONTENT_SETTINGS_TYPE_MEDIASTREAM into CONTENT_SETTINGS_TYPE_MEDIASTREAM_MIC and CONTENT_SETTINGS_TYPE_MEDIASTREAM_CAMERA
# use ContentSetting as value for CONTENT_SETTINGS_TYPE_MEDIASTREAM_MIC/CAMERA, deprecate CONTENT_SETTINGS_TYPE_MEDIASTREAM compound values.
# CONTENT_SETTINGS_TYPE_MEDIASTREAM will be used only for default setting.
# On the content setting media exceptions, show two columns, one for audio and one for video.

BUG=163940
TEST=browser_tests, manual tests like
go to content setting media, use webrtc demo like https://webrtc-demos.appspot.com/html/pc1.html to make an exception, verify the exception show correctly in content settting.

Review URL: https://chromiumcodereview.appspot.com/11316306

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@172302 0039d316-1c4b-4281-b951-d872f2087c98