This CL:
- Removes RenderUtils.
- Creates RenderTestRule with most of the RenderUtils functionality.
- Updates render tests to RenderTestRule.
- Removes the 'regenerate-goldens' flag. This is not needed because the
RenderTestRule will throw an Exception once the test method has
finished, so all image renders and diffs will be saved anyway.
- Simplifies the rendering logic.
BUG=614305
Review-Url: https://codereview.chromium.org/2901053003
Cr-Original-Commit-Position: refs/heads/master@{#474978}
Cr-Mirrored-From: https://chromium.googlesource.com/chromium/src
Cr-Mirrored-Commit: 1c831a5af48331b017f2bf3d6a07abb40f143626
