Add preliminary support for hw-accelerated tile rasterization.

BUG=316685

Review URL: https://codereview.chromium.org/110883015

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@243836 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 243836