[UI Views] Don't allow a ButtonListener and a MenuButtonListener

[UI Views] Don't allow a ButtonListener and a MenuButtonListener

Step 1 in simplifying our button listener logic (and hopefully removing
MenuButtonListener) - ensure each button has at most one listener.

BUG=585252
Committed: https://crrev.com/6cd595e5cf64fe3e3a809291fd870f4a8deac1d5
Cr-Commit-Position: refs/heads/master@{#374462}

[Devlin, 2016-02-09 00:04:20]

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

[Devlin, 2016-02-09 00:04:21]

Scott, mind taking a look?  (Note: this did pass trybots on PS1 [which includes
https://codereview.chromium.org/1671323002/], but Rietveld decided not to show
them.)

[sky, 2016-02-09 04:55:13]

LGTM

[Devlin, 2016-02-09 20:01:27]

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

[Devlin, 2016-02-09 20:01:28]

The patchset sent to the CQ was uploaded after l-g-t-m from sky@chromium.org
Link to the patchset: https://codereview.chromium.org/1682603002/#ps40001
(title: "Latest master")

[commit-bot: I haz the power, 2016-02-09 20:04:43]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1682603002/40001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1682603002/40001

[commit-bot: I haz the power, 2016-02-09 20:52:07]

Committed patchset #3 (id:40001)

[commit-bot: I haz the power, 2016-02-09 20:53:44]

Description was changed from

==========
[UI Views] Don't allow a ButtonListener and a MenuButtonListener

Step 1 in simplifying our button listener logic (and hopefully removing
MenuButtonListener) - ensure each button has at most one listener.

BUG=585252
==========

to

==========
[UI Views] Don't allow a ButtonListener and a MenuButtonListener

Step 1 in simplifying our button listener logic (and hopefully removing
MenuButtonListener) - ensure each button has at most one listener.

BUG=585252

Committed: https://crrev.com/6cd595e5cf64fe3e3a809291fd870f4a8deac1d5
Cr-Commit-Position: refs/heads/master@{#374462}
==========

[commit-bot: I haz the power, 2016-02-09 20:53:46]

Patchset 3 (id:??) landed as
https://crrev.com/6cd595e5cf64fe3e3a809291fd870f4a8deac1d5
Cr-Commit-Position: refs/heads/master@{#374462}