[Mac] On pressing Esc key, close Bookmark Bubble without editing.

[Mac] On pressing Esc key, close Bookmark Bubble without editing.

Dismiss the bubble without updating changes to the node.

BUG=329459
R=asvitkine@chromium.org

TEST=
1. Launch chrome, press "Cmd+Shift+D" to "Show Bookmarks Bar"
2. Navigate to any webpage or new tab & press "Cmd+D" to open bookmark window and then press "Enter" key
3. On the same page, again press "Cmd+D" and change the page name in bookmark bubble window
4. Now press "Esc" key and observe
5. On pressing "Esc" key, bubble should get closed without making any changes to the bookmark

Committed: https://crrev.com/e3ed8486c32c888cc268795c61d4c95e9b07986d
Cr-Commit-Position: refs/heads/master@{#296239}

[Gaja, 2014-09-23 06:27:51]

@asvitkine
PTAL.

[Alexei Svitkine (slow), 2014-09-23 17:00:07]

lgtm

[Gaja, 2014-09-23 17:34:10]

The CQ bit was checked by gajendra.n@samsung.com

[commit-bot: I haz the power, 2014-09-23 17:59:29]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/592323002/1

[commit-bot: I haz the power, 2014-09-23 21:05:59]

Committed patchset #1 (id:1) as 6790ec7a3d7048ccffbe8a70638afad8b1abcf3d

[commit-bot: I haz the power, 2014-09-23 21:06:48]

Patchset 1 (id:??) landed as
https://crrev.com/e3ed8486c32c888cc268795c61d4c95e9b07986d
Cr-Commit-Position: refs/heads/master@{#296239}