Files.app: Show progress bar for file open dialog.

Files.app: Show progress bar for file open dialog.

We have progress bar on dialog footer, and it should show for file open dialog
that needs local cache file for drive files. (e.g. dialog called by NPAPI plugin)

Also the CL adjust mergin so that "Preparing..." label should be placed with the
correct margin no matter if the "New directory" button is shown or not.

BUG=459876
TEST=manually

Committed: https://crrev.com/e213b035d9b557421fc918c055c09bc11b460788
Cr-Commit-Position: refs/heads/master@{#323893}

[hirono, 2015-04-06 05:11:29]

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

[hirono, 2015-04-06 05:11:30]

PTAL, thanks!

[fukino, 2015-04-06 05:19:04]

lgtm!

[hirono, 2015-04-06 05:25:23]

The CQ bit was checked by hirono@chromium.org

[commit-bot: I haz the power, 2015-04-06 05:25:27]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1056413002/1

[hirono, 2015-04-06 05:25:31]

On 2015/04/06 05:19:04, fukino wrote:
> lgtm!

Thanks!

[commit-bot: I haz the power, 2015-04-06 05:35:06]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-04-06 05:35:58]

Patchset 1 (id:??) landed as
https://crrev.com/e213b035d9b557421fc918c055c09bc11b460788
Cr-Commit-Position: refs/heads/master@{#323893}