cros: Arrow key traversal in views.

cros: Arrow key traversal in views.

- Add arrow key traversal to FocusManager; The behavior is default to off;
- Make NativeTextfieldViews::HandleKeyEvent sets |cursor_changed| flag
  only when cursor position changes for left/right arrow key; This allows
  left on most left cursor position and right on the most right position
  to traverse away from the Textfield;
- Login screen to turn on the behavior when kiosk oem manifest asks for it
  and turn if off when the login screen goes away;

BUG=236997, 237550
TBR=zelidrag@chromium.org

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=198064

[xiyuan, 2013-05-02 21:56:06]

Split from https://codereview.chromium.org/14751010/ as CQ seems not like it.

[commit-bot: I haz the power, 2013-05-02 21:58:05]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/xiyuan@chromium.org/14827004/1

[commit-bot: I haz the power, 2013-05-02 22:47:26]

Step "update" is always a major failure.
Look at the try server FAQ for more details.
http://build.chromium.org/p/tryserver.chromium/buildstatus?builder=win_rel&nu...

[commit-bot: I haz the power, 2013-05-03 01:05:42]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/xiyuan@chromium.org/14827004/1

[commit-bot: I haz the power, 2013-05-03 04:56:34]

Change committed as 198064

[msw, 2013-07-25 00:32:53]

Please see http://crbug.com/264054

https://chromiumcodereview.appspot.com/14827004/diff/1/ui/views/controls/text...
File ui/views/controls/textfield/native_textfield_views.cc (right):

https://chromiumcodereview.appspot.com/14827004/diff/1/ui/views/controls/text...
ui/views/controls/textfield/native_textfield_views.cc:1193: cursor_changed =
model_->GetCursorPosition() != cursor_position;
This is wrong and caused a regression, see http://crbug.com/264054
The cursor position may not change, while the selection range does.