Adding skia null gl context sources to chromium's build of skia so it can be used in blink unit tests

BUG=329949

Review URL: https://codereview.chromium.org/140743004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@245375 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 245375
Fix an issue that MediaController is disaled when entering fullscreen

In the old contentVideoView.java, we create the MediaController first in the openVideo() call.
Then we call updateMediaMetadata() to enable to media controller and set the metadata.
With ContentVideoViewLegacy.java, the ordering between updateMediaMetadata() and mediaController creation is reversed. That causes the controller to become disabled.
This change posts a task when RequestMediaMetadata() is called to solve the above issue, and to avoid the reentrance issue.

BUG=334635

Review URL: https://codereview.chromium.org/141243002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@245376 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 245376