[Fullscreen Control] Tweaking touch timeout behavior

Per hwi@'s feedback, the timout should start 5 seconds after the user
releases the finger.

Bug: 758456
Change-Id: I5cd850c9427e2ce792db19c9772121f8ce0bfa52
Reviewed-on: https://chromium-review.googlesource.com/784096
Commit-Queue: Yuwei Huang <yuweih@chromium.org>
Reviewed-by: Robert Liao <robliao@chromium.org>
Cr-Commit-Position: refs/heads/master@{#518742}
1 file changed