Fix the problem that VR desktop take a while to draw and black background of menu bar

Android Chromoting:

1. Fix the problem that VR desktop take a while to draw.
2. Fix the problem that background of menu bar is black before the desktop is drawn.

BUG=516871
Committed: https://crrev.com/0ede6c18c5ba2152dfa0fefe6eedef4166e88507
Cr-Commit-Position: refs/heads/master@{#348693}

[shichengfeng, 2015-09-14 19:06:45]

shichengfeng@google.com changed reviewers:
+ lambroslambrou@chromium.org, sergeyu@chromium.org

[shichengfeng, 2015-09-14 19:07:21]

Fix the problem that VR desktop take a while to draw and black background of
menu bar.

[Lambros, 2015-09-14 19:21:34]

lgtm

[shichengfeng, 2015-09-14 19:28:03]

The CQ bit was checked by shichengfeng@google.com

[commit-bot: I haz the power, 2015-09-14 19:29:08]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1342883002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1342883002/1

[commit-bot: I haz the power, 2015-09-14 19:59:28]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-09-14 20:00:48]

Patchset 1 (id:??) landed as
https://crrev.com/0ede6c18c5ba2152dfa0fefe6eedef4166e88507
Cr-Commit-Position: refs/heads/master@{#348693}

[commit-bot: I haz the power, 2015-09-23 12:36:11]

Patchset 1 (id:??) landed as
https://crrev.com/0ede6c18c5ba2152dfa0fefe6eedef4166e88507
Cr-Commit-Position: refs/heads/master@{#348693}