GitLab

This makes us more consistent in how the ImmersiveFullscreenController
gets enabled. This patch also fixes the UMA for Chrome app windows.

Change-Id: Ib81d7401239cdcf42a415e81b01c29f3f378075c
Reviewed-on: https://chromium-review.googlesource.com/1207213Reviewed-by: Scott Violet <sky@chromium.org>
Commit-Queue: Evan Stade <estade@chromium.org>
Cr-Commit-Position: refs/heads/master@{#589662}