[BGPT] Support kDstIn blend-mode for non-render surface quads

This allows us to remove the render surface for the effect
node representing a rounded-corner mask.

Bug: 926497

Test: multiple web tests exercise these code paths.

Change-Id: I8af37bb94e955a33314f397795b2b9149f29c6d7
Reviewed-on: https://chromium-review.googlesource.com/c/1460306
Reviewed-by: enne <enne@chromium.org>
Commit-Queue: Chris Harrelson <chrishtr@chromium.org>
Cr-Commit-Position: refs/heads/master@{#631511}
15 files changed