Tweak Views Omnibox/Textfield; re-enable OmniboxViewTest.SelectAllOnClick.

Tweak Views Omnibox/Textfield; re-enable OmniboxViewTest.SelectAllOnClick.

Update test expectations for OmniboxViewTest.SelectAllOnClick:
(CrOS used to show/retain unfocused (grey highlight) Omnibox selections)
(My http://crrev.com/183239 made it save/restore selections like Windows)
Don't expect unfocused selections; check that clicking anew selects all.

Move the base omnibox click offset over to the right a little.
(fixes the test for OmniboxViewWin's slightly different hit-test area)
Enable previously USE_AURA-limited code on all TOOLKIT_VIEWS.

Update NativeTextfieldViews::OnMouseDragged to only handle left-click.
(it was incorrectly and incompletely handling right- and middle-drag)
Make NativeTextfieldViews::HandleMousePressEvent focus on right-click.
(it was selecting all and showing the context menu without taking focus)

Use ui_test_utils::IsViewFocused() instead of GetFocusView()->HasFocus(); 
Inline the last remaining GetFocusView call; some refactoring.

BUG=128556, 139069
TEST=None; OmniboxViewTest.SelectAllOnClick passes.
R=derat@chromium.org,sky@chromium.org

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=193404

[msw, 2013-04-10 01:08:09]

Hey Dan and Scott, please take a look; thanks!
Note Cem's similar CL: https://codereview.chromium.org/13084017/
(he may expand the test beyond TOOLKIT_VIEWS in a followup)

[Daniel Erat, 2013-04-10 04:03:37]

lgtm

[sky, 2013-04-10 14:06:40]

LGTM

[commit-bot: I haz the power, 2013-04-10 14:47:00]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/msw@chromium.org/13896002/20001

[commit-bot: I haz the power, 2013-04-10 17:17:31]

Change committed as 193404