Avoid some calls to GpuChannel::Flush.

Some calls are issued specifically to verify that deferred requests
made it to the GPU up to a certain id. If there is a way to verify
that this ID is reached without the IPC then there is no need to
issue the IPC.

This CL establishes a shared memory channel that only contains the
ID and allows skipping the messages. This is very similar to the intervention done in CookieJar to great success performance wise.
(See https://crbug.com/40061885)

Bug: 1500339

Change-Id: Ib63738130dbfcfe3f2b63426b7159fe8d2be4550
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4985693


Reviewed-by: Jonathan Ross <jonross@chromium.org>
Reviewed-by: danakj <danakj@chromium.org>
Commit-Queue: Olivier Li <olivierli@chromium.org>
Reviewed-by: Sunny Sachanandani <sunnyps@chromium.org>
Reviewed-by: Yuzhu Shen <yzshen@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1282152}