Fix auto opening FSP volumes on mount.

Fix auto opening FSP volumes on mount.

Previously, I didn't test it carefully...

TEST=Tested manually.
BUG=427776
Committed: https://crrev.com/f60b0206d617cabb0381a58af3dfdb18bc1b448a
Cr-Commit-Position: refs/heads/master@{#302240}

[mtomasz, 2014-10-31 06:46:59]

mtomasz@chromium.org changed reviewers:
+ hirono@chromium.org

[mtomasz, 2014-10-31 06:47:17]

@hirono: PTAL one more time. The previous fix was buggy. Thanks.

[hirono, 2014-10-31 06:51:48]

lgtm, sorry I noticed the displayRoot can be null, but I misunderstood as it is
initialized at the constructor other than drive volumes...

[mtomasz, 2014-10-31 06:57:29]

On 2014/10/31 06:51:48, hirono wrote:
> lgtm, sorry I noticed the displayRoot can be null, but I misunderstood as it
is
> initialized at the constructor other than drive volumes...

Me the same. Plus I messed up the constant name. Sorry!

[mtomasz, 2014-10-31 06:57:33]

The CQ bit was checked by mtomasz@chromium.org

[commit-bot: I haz the power, 2014-10-31 06:58:17]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/689003002/1

[commit-bot: I haz the power, 2014-10-31 07:41:47]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2014-10-31 07:42:21]

Patchset 1 (id:??) landed as
https://crrev.com/f60b0206d617cabb0381a58af3dfdb18bc1b448a
Cr-Commit-Position: refs/heads/master@{#302240}