We are now using SharedImage to hold the image for the video renderer,
https://chromium-review.googlesource.com/c/chromium/src/+/1616978.
That change, together with the change that made the video be deferred, and
therefore, use the paintRecorder, let us safely remove the workaround.

There was nevertheless the issue of texture lifetime to extend the texture.
If the backend texture is the same in the SkImage and the one contained
in the cache, we will let skia release it. If they are different, cache has
to destroy their own texture, and the one in skia will survive the delete.

Bug: 974656, 991792, 993774, 994516, 996083, 1004780
Change-Id: I10b4165febf14a158584eb2b05cdb8c75c59175e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1815734Reviewed-by: Dan Sanders <sandersd@chromium.org>
Reviewed-by: Khushal <khushalsagar@chromium.org>
Commit-Queue: Juanmi Huertas <juanmihd@chromium.org>
Cr-Commit-Position: refs/heads/master@{#698933}