Disable mouse-focus of buttons in some WebUI pages

Disable mouse-focus of buttons in some WebUI pages.

Introduce FocusManager.disableMouseFocusOnButtons, and use it in uber
navigation, options, history, and NTP.

This is a follow-up change for the fix for crbug.com/89708.

BUG=255405, 255973, 256590
R=arv@chromium.org

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=210973

[tkent, 2013-07-03 01:16:20]

We need to disable mouse-focus globally. Not all pages use focus_manager.js.

Should we put the code to cr.js like the first patch in this CL, or
should we add a function to util.js and call it from every js?

[arv (Not doing code reviews), 2013-07-08 18:32:14]

I don't like making this change globally. It kind of defeats the purpose of
fixing this in the first place.

How about exposing the code that preventsDefault as a method on the FocusManager
and then the WebUI pages that depend on this legacy behavior can opt in by doing
something like

new FocusManager().disableMouseFocusOnInputs()

[tkent, 2013-07-08 23:51:19]

On 2013/07/08 18:32:14, arv wrote:
> I don't like making this change globally. It kind of defeats the purpose of
> fixing this in the first place.
> 
> How about exposing the code that preventsDefault as a method on the
FocusManager
> and then the WebUI pages that depend on this legacy behavior can opt in by
doing
> something like
> 
> new FocusManager().disableMouseFocusOnInputs()

Thank you for the comment.
I updated the patch. It introduces FocusManager.disableMouseFOcusOnButtons().
I didn't make it a normal member function of FocusManager because creating
FocusManager object without calling FocusManager.initialize looks inconsistent.

[arv (Not doing code reviews), 2013-07-10 20:56:42]

LGTM

[commit-bot: I haz the power, 2013-07-10 20:58:47]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/tkent@chromium.org/18593003/7002

[tkent, 2013-07-10 23:56:00]

Committed patchset #2 manually as r210973 (presubmit successful).

[Dan Beam, 2015-02-06 20:20:48]

dbeam@chromium.org changed reviewers:
+ dbeam@chromium.org

[Dan Beam, 2015-02-06 20:20:49]

On 2013/07/08 18:32:14, arv wrote:
> I don't like making this change globally. It kind of defeats the purpose of
> fixing this in the first place.
> 
> How about exposing the code that preventsDefault as a method on the
FocusManager
> and then the WebUI pages that depend on this legacy behavior can opt in by
doing
> something like
> 
> new FocusManager().disableMouseFocusOnInputs()

why do webui pages depend on buttons not getting focus?  i don't see a real
issue with all the bugs this fixes... and so far this code has just been messing
with chrome://* accessibility.