Retain the menu models in the class along with the menu runner.

Retain the menu models in the class along with the menu runner.

The issue was that we were posting an asynchronous accessibility event on
the menu item view, and the menu item view was still around after the menu
closed (just hidden, and owned by the menu runner), but the menu item view's
delegate (the menu model adapter) had gone out of scope.

BUG=327510
NOTRY=true

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=271961

[sky, 2014-05-20 23:38:53]

LGTM

[dmazzoni, 2014-05-21 04:47:34]

The CQ bit was checked by dmazzoni@chromium.org

[commit-bot: I haz the power, 2014-05-21 04:47:56]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/dmazzoni@chromium.org/295903006/1

[dmazzoni, 2014-05-21 17:22:23]

The CQ bit was unchecked by dmazzoni@chromium.org

[dmazzoni, 2014-05-21 17:42:45]

The CQ bit was checked by dmazzoni@chromium.org

[dmazzoni, 2014-05-21 17:43:00]

The CQ bit was unchecked by dmazzoni@chromium.org

[dmazzoni, 2014-05-21 17:43:11]

The CQ bit was checked by dmazzoni@chromium.org

[commit-bot: I haz the power, 2014-05-21 19:57:43]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/dmazzoni@chromium.org/295903006/1

[commit-bot: I haz the power, 2014-05-21 20:27:04]

Change committed as 271961