cc: Convert LTHCommon tests to LayerImpl
Converted these LayerTreeHostCommon tests:
RenderSurfaceListForRenderSurfaceWithClippedLayer
RenderSurfaceTransformsInHighDPI
RenderSurfaceTransformsInHighDPIAccurateScaleZeroPosition
This lets them ask about render surface layer list sizes. It's not that
critical to these tests, but arguably the main thread doesn't need to
know about screen space transforms either.
R=weiliangc@chromium.org
BUG=504466
CQ_INCLUDE_TRYBOTS=tryserver.blink:linux_blink_rel
Review URL: https://codereview.chromium.org/
1252263003
Cr-Commit-Position: refs/heads/master@{#340483}