Refactor DisplayListCanvas, RecordingCanvas, and SkiaCanvas to share a common API. Change-Id: I0268ec2749ea5d13a3a72bb2784ed6a9911383d9
Removes obsolete drawPosText codepath, and unifies text decoration behavior. Change-Id: I9c563249ab688a3394445a0e7fe1b9d0661f6f7c