aw: Enable ipc-based sync compositing by default
aw: Enable ipc-based sync compositing by default

Only temprarily though to gather perf and compatibility results.

BUG=583455

Previous Committed:
https://crrev.com/315cb6bb87f60fdc3a8b8c706b32556ecebf4c17
Cr-Commit-Position: refs/heads/master@{#374387}

Review URL: https://codereview.chromium.org/1687473002

Cr-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#375008}

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