[Extensions Toolbar] Properly render newly-added extensions

[Extensions Toolbar] Properly render newly-added extensions

Fix a regression where newly-added extensions were not properly drawn.
Also have the newly-installed extension button stop tracking, so it doesn't try
to set state when the popup closes.

BUG=433817
Committed: https://crrev.com/ebcd353dbbfff82230807a5d81dd8cd1b9b8441e
Cr-Commit-Position: refs/heads/master@{#304503}

[Devlin, 2014-11-17 20:04:38]

rdevlin.cronin@chromium.org changed reviewers:
+ avi@chromium.org

[Devlin, 2014-11-17 20:06:33]

rdevlin.cronin@chromium.org changed reviewers:
+ rsesek@chromium.org

[Devlin, 2014-11-17 20:06:33]

Looks like Avi's OOO - rsesek@, mind taking this one?

[Robert Sesek, 2014-11-17 21:51:47]

How does this fix the NULL deref in the attached BUG=?

[Devlin, 2014-11-17 21:54:26]

On 2014/11/17 21:51:47, Robert Sesek wrote:
> How does this fix the NULL deref in the attached BUG=?

Whoops, wrong bug linked.  Sorry about that.  Should be right, now.

[Robert Sesek, 2014-11-17 21:55:46]

LGTM

[Devlin, 2014-11-17 21:58:15]

The CQ bit was checked by rdevlin.cronin@chromium.org

[commit-bot: I haz the power, 2014-11-17 21:59:42]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/732203002/1

[commit-bot: I haz the power, 2014-11-17 22:51:13]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2014-11-17 22:52:45]

Patchset 1 (id:??) landed as
https://crrev.com/ebcd353dbbfff82230807a5d81dd8cd1b9b8441e
Cr-Commit-Position: refs/heads/master@{#304503}

[Michael Achenbach, 2014-11-18 08:29:42]

A revert of this CL (patchset #1 id:1) has been created in
https://codereview.chromium.org/736643002/ by machenbach@chromium.org.

The reason for reverting is: [Sheriff] Makes
ExtensionActionContextMenuControllerTest.BrowserAction flaky on Mac and Mac dbg:

Starting here:
http://build.chromium.org/p/chromium.mac/builders/Mac10.6%20Tests/builds/681
http://build.chromium.org/p/chromium.mac/builders/Mac10.9%20Tests%20%28dbg%29....