Gallery: change size of crop overlay to cover entire window.

Gallery: change size of crop overlay to cover entire window.

Previously, size of crop overlay was same with it of an image. But since
size calculation logics for crop overlay and an image are different, it
causes gaps as issues describe. This CL changes crop overlay to cover
entier window.

BUG=498783, 516638
TEST=manually tested as described in the issues.

Committed: https://crrev.com/bf3ca37da6d0007be86a963b98b79353176b0baf
Cr-Commit-Position: refs/heads/master@{#342321}

[yawano, 2015-08-07 06:39:07]

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

[yawano, 2015-08-07 06:39:08]

PTAL. Thank you!

[hirono, 2015-08-07 08:05:38]

lgtm

[yawano, 2015-08-07 08:15:20]

On 2015/08/07 08:05:38, hirono wrote:
> lgtm

Thank you!

[yawano, 2015-08-07 08:15:23]

The CQ bit was checked by yawano@chromium.org

[commit-bot: I haz the power, 2015-08-07 08:15:34]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1281823002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1281823002/1

[commit-bot: I haz the power, 2015-08-07 08:44:33]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-08-07 08:45:16]

Patchset 1 (id:??) landed as
https://crrev.com/bf3ca37da6d0007be86a963b98b79353176b0baf
Cr-Commit-Position: refs/heads/master@{#342321}