Add key to focus infobars

Add key to focus infobars

On Windows & Chrome OS, pressing Alt+Shift+A will bring focus to the first
control in the first infobar, if any are shown. No reason for 'A' - 'I' is
already taken on Chrome OS, but all other hotkeys to directly focus a given
pane are Alt+Shift+Letter shortcuts.

BUG=226334
Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=195030

[Ben Goodger (Google), 2013-04-18 18:19:37]

lgtm

[commit-bot: I haz the power, 2013-04-18 18:22:23]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/dmazzoni@chromium.org/14225016/1

[commit-bot: I haz the power, 2013-04-18 22:06:40]

Retried try job too often on win7_aura for step(s) browser_tests
http://build.chromium.org/p/tryserver.chromium/buildstatus?builder=win7_aura&...

[commit-bot: I haz the power, 2013-04-18 23:16:45]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/dmazzoni@chromium.org/14225016/1

[commit-bot: I haz the power, 2013-04-19 00:49:24]

Change committed as 195030

[Peter Kasting, 2013-04-19 00:52:57]

I would have suggested "N", as that's the second letter of infobar, and at least
for English, sounds like the beginning of the word "infobar".  OTOH, users
probably have no idea we call these "infobars".

I don't really know why this patch is a win.  You said it would be in comment 6
on the linked bug, but lacking an accessibility background, I don't know why
putting the controls in the tab order is insufficient, or how users are supposed
to discover this key shortcut.

[dmazzoni, 2013-04-19 05:22:41]

See bug for more context. This is in direct response to blind users who heard
the announcement of the text of the infobar when it appeared, but had trouble
figuring out how to respond.

For Chrome OS in particular, I'm working on a subsequent change that will
announce the presence and also announce a key to press. The new announcement
would be something like:

Page has 1 alert: "google.com would like to use your location" - to review,
press Alt+Shift+A.