Redesigns the text input focus handling.

ui/views/ime/null_input_method.h

Index: ui/views/ime/null_input_method.h
diff --git a/ui/views/ime/null_input_method.h b/ui/views/ime/null_input_method.h
new file mode 100644
index 0000000000000000000000000000000000000000..2714c90c625b6882f1ebfff340498cb1bf2c4b5f
--- /dev/null
+++ b/ui/views/ime/null_input_method.h
@@ -0,0 +1,51 @@
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef UI_VIEWS_IME_NULL_INPUT_METHOD_H_
+#define UI_VIEWS_IME_NULL_INPUT_METHOD_H_
+
+#include "base/compiler_specific.h"
+#include "base/macros.h"

[msw, 2014/03/11 00:58:50]

nit: is this explicitly needed here?

[Yuki, 2014/03/11 15:27:37]

base/compiler_specific.h is for OVERRIDE macro.
base/macros.h is for DISALLOW_COPY_AND_ASSIGN macro.

Since views::InputMethod (input_method.h) doesn't use either of them, I thought
we should include them here.  However, ui/views/ime/input_method.h indirectly
includes them, so technically we don't need to include them explicitly here.

I think that depending indirect #include could be problematic.  If those
indirect headers are changed, there is no guarantee that this file compiles. 
So, in order to follow the include-what-you-use rule, I think we should include
them here explicitly.

[msw, 2014/03/11 23:24:37]

Sounds good.

+#include "ui/views/ime/input_method.h"
+
+namespace views {
+
+// An implementation of views::InputMethod which does nothing.
+//
+// We're working on removing views::InputMethod and all its family and going

[msw, 2014/03/11 00:58:50]

nit: I'm not sure what you mean by "family", please revise.

[Yuki, 2014/03/11 15:27:37]

Done.

+// to use only ui::InputMethod.  This class allows us to disable all the effects
+// come from views::InputMethodBridge by replacing it with this instance,

[msw, 2014/03/11 00:58:50]

nit: "that come from"

[Yuki, 2014/03/11 15:27:37]

Done.

+// without a big interface change.  This class also enables that we can switch

[msw, 2014/03/11 00:58:50]

This sentence and the above needs some grammar work; instead consider: "Use this
class instead of views::InputMethodBridge with ui::TextInputFocusManager to
effectively eliminate the views::InputMethod layer."

[Yuki, 2014/03/11 15:27:37]

Done.

+// between with and without views::InputMethodBridge in an easy way.
+class NullInputMethod : public InputMethod {
+ public:
+  NullInputMethod();
+
+  // Overridden from InputMethod:
+  virtual void SetDelegate(internal::InputMethodDelegate* delegate) OVERRIDE;
+  virtual void Init(Widget* widget) OVERRIDE;
+  virtual void OnFocus() OVERRIDE;
+  virtual void OnBlur() OVERRIDE;
+  virtual bool OnUntranslatedIMEMessage(const base::NativeEvent& event,
+                                        NativeEventResult* result) OVERRIDE;
+  virtual void DispatchKeyEvent(const ui::KeyEvent& key) OVERRIDE;
+  virtual void OnTextInputTypeChanged(View* view) OVERRIDE;
+  virtual void OnCaretBoundsChanged(View* view) OVERRIDE;
+  virtual void CancelComposition(View* view) OVERRIDE;
+  virtual void OnInputLocaleChanged() OVERRIDE;
+  virtual std::string GetInputLocale() OVERRIDE;
+  virtual bool IsActive() OVERRIDE;
+  virtual ui::TextInputClient* GetTextInputClient() const OVERRIDE;
+  virtual ui::TextInputType GetTextInputType() const OVERRIDE;
+  virtual bool IsCandidatePopupOpen() const OVERRIDE;
+  virtual void ShowImeIfNeeded() OVERRIDE;
+  virtual bool IsMock() const OVERRIDE;
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(NullInputMethod);
+};
+
+}  // namespace views
+
+#endif  // UI_VIEWS_IME_NULL_INPUT_METHOD_H_