Fix InputMethod Widget activation checks; cleanup, etc.

Fix InputMethod Widget activation checks; cleanup, etc.

Remove InputMethodBase::On[Focus|Blur] and |widget_focused_|.
Check widget()->IsActive() as needed instead of widget_focused_.
( this resolves improper init order firing DCHECKs in views_unittests )
( fixes FocusManagerDtorTest.* with --enable-views-textfield )
Fix NativeTextfieldViewsTest widget activation and textfield focus.

Rename virtual InputMethod::set_delegate() to SetDelegate().
Call the base Init from InputMethodBase::Init first.
( initializes |widget_| before it's used in OnInputLangChange )
Remove InputMethodBase's unnecessary NON_EXPORTED_BASE usage.
Add empty MockInputMethod::On[Focus|Blur] implementations.
Update comments for conciseness and clarity.

BUG=131660
TEST=No input regressions; unit tests pass with --enable-views-textfield.
R=sky@chromium.org,suzhe@chromium.org

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=191049

[msw, 2013-03-26 18:39:26]

Hey James and Scott, please take a look; thanks!

[msw, 2013-03-26 19:33:07]

Gah, hold off for linux_chromeos test failures...
I'm really disliking our IME code...

[msw, 2013-03-27 01:55:09]

Please take a look now, thanks! Fixing views_unittests was simple enough.

[James Su, 2013-03-27 03:12:32]

On 2013/03/27 01:55:09, msw wrote:
> Please take a look now, thanks! Fixing views_unittests was simple enough.

LGTM

[sky, 2013-03-27 15:10:23]

https://codereview.chromium.org/12902029/diff/11002/ui/views/ime/input_method...
File ui/views/ime/input_method_base.cc (right):

https://codereview.chromium.org/12902029/diff/11002/ui/views/ime/input_method...
ui/views/ime/input_method_base.cc:18: if (widget())
Is this needed? You don't null check widget any where else. Also, I would be
inclined to use widget_ every where rather than widget_ (otherwise places like
this look inconsistant).

[msw, 2013-03-27 17:36:25]

Comments addressed; please take another look.

https://codereview.chromium.org/12902029/diff/11002/ui/views/ime/input_method...
File ui/views/ime/input_method_base.cc (right):

https://codereview.chromium.org/12902029/diff/11002/ui/views/ime/input_method...
ui/views/ime/input_method_base.cc:18: if (widget())
On 2013/03/27 15:10:23, sky wrote:
> Is this needed? You don't null check widget any where else. Also, I would be
> inclined to use widget_ every where rather than widget_ (otherwise places like
> this look inconsistant).

Done; I removed the check, but will restore it if trybots fail. It's possible
that some InputMethod instances may not be Init()'ed with a valid Widget, given
the state of this code.

Done; presuming you meant "rather than widget()", I changed to use widget_
everywhere in this file. I generally prefer to consistently use accessors for
const usages and member identifiers for assignment, so that assignment
statements like "x_ = y" and "x_(y)" are more readily apparent/searchable. I
think you've dissented of that practice before, but I'm still inclined to
generally follow it; let me know if that's an issue and we can figure it out.

[msw, 2013-03-27 20:36:58]

Scott, please take another look; trybots passed and skipping the check works
fine locally; thanks!

[sky, 2013-03-27 20:48:37]

SLGTM

[commit-bot: I haz the power, 2013-03-27 20:55:43]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/msw@chromium.org/12902029/23001

[commit-bot: I haz the power, 2013-03-27 22:19:34]

Change committed as 191049