Smart layer invalidation for LCD text.

When LCD text needs to be disabled for a layer, we can invalidate just the tiles containing text.
This only works with impl-side painting where it is very cheap to mark tiles that have text.

BUG=181245


Review URL: https://chromiumcodereview.appspot.com/13726013

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@192936 0039d316-1c4b-4281-b951-d872f2087c98
11 files changed