Rename SkCanvasVideoRenderer to PaintCanvasVideoRenderer

As the comment in skcanvas_video_renderer.h by enne@,
Rename SkCanvasVideoRenderer to PaintCanvasVideoRenderer
and related class. Rename the files also.

BUG=

Signed-off-by: zhuoyu.qian <zhuoyu.qian@samsung.com>
Cq-Include-Trybots: master.tryserver.blink:linux_trusty_blink_rel
Change-Id: If018d84bb51a02a8a3d310f6f50429da8c444394
Reviewed-on: https://chromium-review.googlesource.com/706881
Commit-Queue: Chris Watkins <watk@chromium.org>
Reviewed-by: Chris Watkins <watk@chromium.org>
Reviewed-by: Dmitry Gozman <dgozman@chromium.org>
Reviewed-by: Nick Carter <nick@chromium.org>
Reviewed-by: enne <enne@chromium.org>
Cr-Commit-Position: refs/heads/master@{#508979}

diff --git a/cc/paint/paint_canvas.h b/cc/paint/paint_canvas.h
index 7a7c75d7..3d35c02 100644
--- a/cc/paint/paint_canvas.h
+++ b/cc/paint/paint_canvas.h

@@ -33,7 +33,7 @@
 
   // TODO(enne): It would be nice to get rid of flush() entirely, as it
   // doesn't really make sense for recording.  However, this gets used by
-  // SkCanvasVideoRenderer which takes a PaintCanvas to paint both
+  // PaintCanvasVideoRenderer which takes a PaintCanvas to paint both
   // software and hardware video.  This is super entangled with ImageBuffer
   // and canvas/video painting in Blink where the same paths are used for
   // both recording and gpu work.