Mac OOP-R GPU crashes: Flush during command decode

Just flushing before and after DoRasterCHROMIUM was not enough to
prevent crashes. In fact, it appears that DoRasterCHROMIUM's behavior
is unrelated to crashes.

Flush after every segment of decoded commands. If this limits crash
rates (it likely will because that worked for non-OOP raster), then we
can start examining the actual commands that were run to find patterns.

Remove old no-longer-needed instrumentation.

Bug: 906453
Change-Id: Ic5faa5a07dbb4223219a3e88a97b5afaeb65d6b7
Reviewed-on: https://chromium-review.googlesource.com/c/1400772
Reviewed-by: Victor Miura <vmiura@chromium.org>
Commit-Queue: ccameron <ccameron@chromium.org>
Cr-Commit-Position: refs/heads/master@{#622120}
4 files changed