Files.app: Use <button> instead of <paper-button> to make ENTER and SPACE effective on them.

Files.app: Use <button> instead of <paper-button> to make ENTER and SPACE effective on them.

<paper-button> does not handle ENTER and SPACE by default, so this CL change
the buttons to <button>s.
<button>s on the footer already have style similar to paper-button, so the
visual style for each button is not changed.

BUG=461758
TEST=manually check the response for ENTER/SPACE

Committed: https://crrev.com/aab6df45d814cd913a0401af812f8ac89d6017b4
Cr-Commit-Position: refs/heads/master@{#318036}

[fukino, 2015-02-25 11:13:33]

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

[fukino, 2015-02-25 11:13:34]

PTAL. Thanks!

[yawano, 2015-02-25 11:26:41]

Could you check that the following selector is affected by this change or not?
Thank you!

https://code.google.com/p/chromium/codesearch#chromium/src/ui/file_manager/in...

[fukino, 2015-02-25 11:44:40]

On 2015/02/25 11:26:41, yawano wrote:
> Could you check that the following selector is affected by this change or not?
> Thank you!
> 
>
https://code.google.com/p/chromium/codesearch#chromium/src/ui/file_manager/in...

Thanks! I updated the test. Could you take another look?

FYI: the class '.button-panel' is added by dialog-footer.js

[yawano, 2015-02-25 12:08:39]

lgtm. Thank you!

[fukino, 2015-02-25 12:59:28]

The CQ bit was checked by fukino@chromium.org

[commit-bot: I haz the power, 2015-02-25 12:59:55]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/944683003/20001

[commit-bot: I haz the power, 2015-02-25 13:34:22]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2015-02-25 13:34:46]

Patchset 2 (id:??) landed as
https://crrev.com/aab6df45d814cd913a0401af812f8ac89d6017b4
Cr-Commit-Position: refs/heads/master@{#318036}