We process the pending messages immediately if these messages matches
the pattern of SwapBuffers, for example, GLRenderer always issues
SwapBuffers calls with a specific IPC message patterns, it should always
be SetLatencyInfo->AsyncFlush->Echo sequence.
Instead of posting a task to message loop, it could avoid the possibility
of being blocked by other channels, and make SwapBuffers executed as soon
as possible.
BUG=407529
Review URL: https://codereview.chromium.org/495313003
Cr-Commit-Position: refs/heads/master@{#292768}
2 files changed
