IME (input method editor) support for Aura, part 1 of 3: Add ui/base/ime/ classes.

ui::InputMethod: 
- An interface similar to views::InputMethod, but does not have Has neither Views nor Aura dependencies. 

ui::InputMethodIBus 
- Port of views::InputMethodIBus. Has neither Views nor Aura dependencies. 

Original review: http://codereview.chromium.org/8576005/ (PatchSet #1-8, Comment #1-24)

BUG=97261
TEST=see part 3 of 3.


Review URL: http://codereview.chromium.org/8659033

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@113095 0039d316-1c4b-4281-b951-d872f2087c98

ui/base/ime/input_method.h

+// Copyright (c) 2011 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_BASE_IME_INPUT_METHOD_H_
+#define UI_BASE_IME_INPUT_METHOD_H_
+#pragma once
+
+#include <string>
+
+#include "base/basictypes.h"
+#include "base/event_types.h"
+#include "base/i18n/rtl.h"
+#include "ui/base/ime/text_input_type.h"
+#include "ui/base/keycodes/keyboard_codes.h"
+#include "ui/base/ui_export.h"
+
+namespace ui {
+
+namespace internal {
+class InputMethodDelegate;
+}  // namespace internal
+
+class TextInputClient;
+
+// An interface implemented by an object that encapsulates a native input method
+// service provided by the underlying operating system, and acts as a "system
+// wide" input method for all Chrome windows. A class that implements this
+// interface should behave as follows:
+// - Receives a keyboard event directly from a message dispatcher for the
+//   system through the InputMethod::DispatchKeyEvent API, and forwards it to
+//   an underlying input method for the OS.
+// - The input method should handle the key event either of the following ways:
+//   1) Send the original key down event to the focused window, which is e.g.
+//      a NativeWidgetAura (NWA) or a RenderWidgetHostViewAura (RWHVA), using
+//      internal::InputMethodDelegate::DispatchKeyEventPostIME API, then send
+//      a Char event using TextInputClient::InsertChar API to a text input
+//      client, which is, again, e.g. NWA or RWHVA, and then send the original
+//      key up event to the same window.
+//   2) Send VKEY_PROCESSKEY event to the window using the DispatchKeyEvent API,
+//      then update IME status (e.g. composition text) using TextInputClient,
+//      and then send the original key up event to the window.
+// - Keeps track of the focused TextInputClient to see which client can call
+//   APIs, OnTextInputTypeChanged, OnCaretBoundsChanged, and CancelComposition,
+//   that change the state of the input method.
+// In Aura environment, aura::DesktopHost creates an instance of ui::InputMethod
+// and owns it.
+class UI_EXPORT InputMethod {
+ public:
+  virtual ~InputMethod() {}
+
+  // Sets the delegate used by this InputMethod instance. It should only be
+  // called by an object which manages the whole UI (e.g. aura::DesktopHost).
+  virtual void SetDelegate(internal::InputMethodDelegate* delegate) = 0;
+
+  // Initializes the InputMethod object. Pass true if the system toplevel window
+  // already has keyboard focus.
+  virtual void Init(bool focused) = 0;
+
+  // Called when the top-level system window gets keyboard focus.
+  virtual void OnFocus() = 0;
+
+  // Called when the top-level system window loses keyboard focus.
+  virtual void OnBlur() = 0;
+
+  // Sets the text input client which receives text input events such as
+  // SetCompositionText(). |client| can be NULL. A gfx::NativeWindow which
+  // implementes TextInputClient interface, e.g. NWA and RWHVA, should register
+  // itself by calling the method when it is focused, and unregister itself by
+  // calling the metho with NULL when it is unfocused.
+  virtual void SetFocusedTextInputClient(TextInputClient* client) = 0;
+
+  // Gets the current text input client. Returns NULL when no client is set.
+  virtual TextInputClient* GetTextInputClient() const = 0;
+
+  // Dispatches a key event to the input method. The key event will be
+  // dispatched back to the caller via
+  // ui::InputMethodDelegate::DispatchKeyEventPostIME(), once it's processed by
+  // the input method. It should only be called by a message dispatcher.
+  virtual void DispatchKeyEvent(const base::NativeEvent& native_key_event) = 0;
+
+  // TODO(yusukes): Add DispatchFabricatedKeyEvent to support virtual keyboards.
+
+  // Called by the focused client whenever its text input type is changed.
+  // Before calling this method, the focused client must confirm or clear
+  // existing composition text and call InputMethod::CancelComposition() when
+  // necessary. Otherwise unexpected behavior may happen. This method has no
+  // effect if the client is not the focused client.
+  virtual void OnTextInputTypeChanged(const TextInputClient* client) = 0;
+
+  // Called by the focused client whenever its caret bounds is changed.
+  // This method has no effect if the client is not the focused client.
+  virtual void OnCaretBoundsChanged(const TextInputClient* client) = 0;
+
+  // Called by the focused client to ask the input method cancel the ongoing
+  // composition session. This method has no effect if the client is not the
+  // focused client.
+  virtual void CancelComposition(const TextInputClient* client) = 0;
+
+  // Returns the locale of current keyboard layout or input method, as a BCP-47
+  // tag, or an empty string if the input method cannot provide it.
+  virtual std::string GetInputLocale() = 0;
+
+  // Returns the text direction of current keyboard layout or input method, or
+  // base::i18n::UNKNOWN_DIRECTION if the input method cannot provide it.
+  virtual base::i18n::TextDirection GetInputTextDirection() = 0;
+
+  // Checks if the input method is active, i.e. if it's ready for processing
+  // keyboard event and generate composition or text result.
+  // If the input method is inactive, then it's not necessary to inform it the
+  // changes of caret bounds and text input type.
+  // Note: character results may still be generated and sent to the text input
+  // client by calling TextInputClient::InsertChar(), even if the input method
+  // is not active.
+  virtual bool IsActive() = 0;
+
+  // Gets the text input type of the focused text input client. Returns
+  // ui::TEXT_INPUT_TYPE_NONE if there is no focused client.
+  virtual TextInputType GetTextInputType() const = 0;
+};
+
+}  // namespace ui
+
+#endif  // UI_BASE_IME_INPUT_METHOD_H_

ui/base/ime/input_method_base.cc

+// Copyright (c) 2011 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.
+
+#include "ui/base/ime/input_method_base.h"
+
+#include "base/logging.h"
+#include "ui/base/ime/input_method_delegate.h"
+#include "ui/base/ime/text_input_client.h"
+
+namespace ui {
+
+InputMethodBase::InputMethodBase()
+  : delegate_(NULL),
+    text_input_client_(NULL),
+    system_toplevel_window_focused_(false) {
+}
+
+InputMethodBase::~InputMethodBase() {
+}
+
+void InputMethodBase::SetDelegate(
+    internal::InputMethodDelegate* delegate) {
+  delegate_ = delegate;
+}
+
+void InputMethodBase::Init(bool focused) {
+  if (focused)
+    OnFocus();
+}
+
+void InputMethodBase::OnFocus() {
+  DCHECK(!system_toplevel_window_focused_);
+  system_toplevel_window_focused_ = true;
+}
+
+void InputMethodBase::OnBlur() {
+  DCHECK(system_toplevel_window_focused_);
+  system_toplevel_window_focused_ = false;
+}
+
+void InputMethodBase::SetFocusedTextInputClient(TextInputClient* client) {
+  TextInputClient* old = text_input_client_;
+  OnWillChangeFocusedClient(old, client);
+  text_input_client_ = client;  // NULL allowed.
+  OnDidChangeFocusedClient(old, client);
+}
+
+TextInputClient* InputMethodBase::GetTextInputClient() const {
+  return system_toplevel_window_focused_ ? text_input_client_ : NULL;
+}
+
+void InputMethodBase::OnTextInputTypeChanged(const TextInputClient* client) {
+  if (!IsTextInputClientFocused(client))
+    return;
+  // TODO(yusukes): Support TextInputTypeTracker for TOUCH_UI.
+}
+
+TextInputType InputMethodBase::GetTextInputType() const {
+  TextInputClient* client = GetTextInputClient();
+  return client ? client->GetTextInputType() : TEXT_INPUT_TYPE_NONE;
+}
+
+bool InputMethodBase::IsTextInputClientFocused(const TextInputClient* client) {
+  return client && (client == GetTextInputClient());
+}
+
+bool InputMethodBase::IsTextInputTypeNone() const {
+  return GetTextInputType() == TEXT_INPUT_TYPE_NONE;
+}
+
+void InputMethodBase::OnInputMethodChanged() const {
+  TextInputClient* client = GetTextInputClient();
+  if (client && client->GetTextInputType() != TEXT_INPUT_TYPE_NONE)
+    client->OnInputMethodChanged();
+}
+
+void InputMethodBase::DispatchKeyEventPostIME(
+    const base::NativeEvent& native_event) const {
+  if (delegate_)
+    delegate_->DispatchKeyEventPostIME(native_event);
+}
+
+void InputMethodBase::DispatchFabricatedKeyEventPostIME(EventType type,
+                                                        KeyboardCode key_code,
+                                                        int flags) const {
+  if (delegate_)
+    delegate_->DispatchFabricatedKeyEventPostIME(type, key_code, flags);
+}
+
+}  // namespace ui

ui/base/ime/input_method_base.h

+// Copyright (c) 2011 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_BASE_IME_INPUT_METHOD_BASE_H_
+#define UI_BASE_IME_INPUT_METHOD_BASE_H_
+#pragma once
+
+#include "base/basictypes.h"
+#include "base/compiler_specific.h"
+#include "ui/base/events.h"
+#include "ui/base/ime/input_method.h"
+#include "ui/base/ui_export.h"
+
+namespace gfx {
+class Rect;
+}  // namespace gfx
+
+namespace ui {
+
+class TextInputClient;
+
+// A helper class providing functionalities shared among ui::InputMethod
+// implementations.
+class UI_EXPORT InputMethodBase : public InputMethod {
+ public:
+  InputMethodBase();
+  virtual ~InputMethodBase();
+
+  // Overriden from InputMethod.
+  virtual void SetDelegate(internal::InputMethodDelegate* delegate) OVERRIDE;
+  virtual void Init(bool focused) OVERRIDE;
+  // If a derived class overrides OnFocus()/OnBlur(), it should call parent's
+  // implementation first, to make sure |system_toplevel_window_focused_| flag
+  // can be updated correctly.
+  virtual void OnFocus() OVERRIDE;
+  virtual void OnBlur() OVERRIDE;
+  virtual void SetFocusedTextInputClient(TextInputClient* client) OVERRIDE;
+  virtual TextInputClient* GetTextInputClient() const OVERRIDE;
+
+  // If a derived class overrides this method, it should call parent's
+  // implementation.
+  virtual void OnTextInputTypeChanged(const TextInputClient* client) OVERRIDE;
+
+  virtual TextInputType GetTextInputType() const OVERRIDE;
+
+ protected:
+  virtual void OnWillChangeFocusedClient(TextInputClient* focused_before,
+                                         TextInputClient* focused) {}
+  virtual void OnDidChangeFocusedClient(TextInputClient* focused_before,
+                                        TextInputClient* focused) {}
+
+  // Returns true if |client| is currently focused.
+  bool IsTextInputClientFocused(const TextInputClient* client);
+
+  // Checks if the focused text input client's text input type is
+  // TEXT_INPUT_TYPE_NONE. Also returns true if there is no focused text
+  // input client.
+  bool IsTextInputTypeNone() const;
+
+  // Convenience method to call the focused text input client's
+  // OnInputMethodChanged() method. It'll only take effect if the current text
+  // input type is not TEXT_INPUT_TYPE_NONE.
+  void OnInputMethodChanged() const;
+
+  // Convenience method to call delegate_->DispatchKeyEventPostIME().
+  void DispatchKeyEventPostIME(const base::NativeEvent& native_event) const;
+
+  // Convenience method to call delegate_->DispatchFabricatedKeyEventPostIME().
+  void DispatchFabricatedKeyEventPostIME(EventType type,
+                                         KeyboardCode key_code,
+                                         int flags) const;
+
+  bool system_toplevel_window_focused() const {
+    return system_toplevel_window_focused_;
+  }
+
+ private:
+  internal::InputMethodDelegate* delegate_;
+  TextInputClient* text_input_client_;
+
+  bool system_toplevel_window_focused_;
+
+  DISALLOW_COPY_AND_ASSIGN(InputMethodBase);
+};
+
+}  // namespace ui
+
+#endif  // UI_BASE_IME_INPUT_METHOD_BASE_H_

ui/base/ime/input_method_delegate.h

+// Copyright (c) 2011 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_BASE_IME_INPUT_METHOD_DELEGATE_H_
+#define UI_BASE_IME_INPUT_METHOD_DELEGATE_H_
+#pragma once
+
+#include "base/event_types.h"
+#include "ui/base/events.h"
+#include "ui/base/ui_export.h"
+
+namespace ui {
+namespace internal {
+
+// An interface implemented by the object that handles events sent back from an
+// ui::InputMethod implementation.
+class UI_EXPORT InputMethodDelegate {
+ public:
+  virtual ~InputMethodDelegate() {}
+
+  // Dispatch a key event already processed by the input method.
+  virtual void DispatchKeyEventPostIME(
+      const base::NativeEvent& native_key_event) = 0;
+  virtual void DispatchFabricatedKeyEventPostIME(ui::EventType type,
+                                                 ui::KeyboardCode key_code,
+                                                 int flags) = 0;
+};
+
+}  // namespace internal
+}  // namespace ui
+
+#endif  // UI_BASE_IME_INPUT_METHOD_DELEGATE_H_

ui/base/ime/input_method_ibus.h

+// Copyright (c) 2011 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_BASE_IME_INPUT_METHOD_IBUS_H_
+#define UI_BASE_IME_INPUT_METHOD_IBUS_H_
+#pragma once
+
+#include <set>
+#include <string>
+
+#include "base/basictypes.h"
+#include "base/compiler_specific.h"
+#include "base/memory/scoped_ptr.h"
+#include "ui/base/glib/glib_integers.h"
+#include "ui/base/glib/glib_signal.h"
+#include "ui/base/ime/character_composer.h"
+#include "ui/base/ime/composition_text.h"
+#include "ui/base/ime/input_method_base.h"
+
+// Forward declarations, so that we don't need to include ibus.h in this file.
+typedef struct _GAsyncResult GAsyncResult;
+typedef struct _IBusBus IBusBus;
+typedef struct _IBusInputContext IBusInputContext;
+typedef struct _IBusText IBusText;
+
+namespace ui {
+
+// A ui::InputMethod implementation based on IBus.
+class UI_EXPORT InputMethodIBus : public InputMethodBase {
+ public:
+  explicit InputMethodIBus(internal::InputMethodDelegate* delegate);
+  virtual ~InputMethodIBus();
+
+  // Overridden from InputMethod:
+  virtual void OnFocus() OVERRIDE;
+  virtual void OnBlur() OVERRIDE;
+  virtual void Init(bool focused) OVERRIDE;
+  virtual void DispatchKeyEvent(
+      const base::NativeEvent& native_key_event) OVERRIDE;
+  virtual void OnTextInputTypeChanged(const TextInputClient* client) OVERRIDE;
+  virtual void OnCaretBoundsChanged(const TextInputClient* client) OVERRIDE;
+  virtual void CancelComposition(const TextInputClient* client) OVERRIDE;
+  virtual std::string GetInputLocale() OVERRIDE;
+  virtual base::i18n::TextDirection GetInputTextDirection() OVERRIDE;
+  virtual bool IsActive() OVERRIDE;
+
+ private:
+  // A class to hold all data related to a key event being processed by the
+  // input method but still has no result back yet.
+  class PendingKeyEvent;
+
+  // A class to hold information of a pending request for creating an ibus input
+  // context.
+  class PendingCreateICRequest;
+
+  // Overridden from InputMethodBase:
+  virtual void OnWillChangeFocusedClient(TextInputClient* focused_before,
+                                         TextInputClient* focused) OVERRIDE;
+  virtual void OnDidChangeFocusedClient(TextInputClient* focused_before,
+                                        TextInputClient* focused) OVERRIDE;
+
+  // Creates |context_| instance asynchronously.
+  void CreateContext();
+
+  // Sets |context_| and hooks necessary signals.
+  void SetContext(IBusInputContext* ic);
+
+  // Destroys |context_| instance.
+  void DestroyContext();
+
+  // Asks the client to confirm current composition text.
+  void ConfirmCompositionText();
+
+  // Resets |context_| and abandon all pending results and key events.
+  void ResetContext();
+
+  // Checks the availability of focused text input client and update focus state
+  // of |context_|.
+  void UpdateContextFocusState();
+
+  // Process a key returned from the input method.
+  void ProcessKeyEventPostIME(const base::NativeEvent& native_key_event,
+                              guint32 ibus_keycode,
+                              bool handled);
+
+  // Processes a key event that was already filtered by the input method.
+  // A VKEY_PROCESSKEY may be dispatched to the focused View.
+  void ProcessFilteredKeyPressEvent(const base::NativeEvent& native_key_event);
+
+  // Processes a key event that was not filtered by the input method.
+  void ProcessUnfilteredKeyPressEvent(const base::NativeEvent& native_key_event,
+                                      guint32 ibus_keycode);
+  void ProcessUnfilteredFabricatedKeyPressEvent(EventType type,
+                                                KeyboardCode key_code,
+                                                int flags,
+                                                guint32 ibus_keyval);
+
+  // Sends input method result caused by the given key event to the focused text
+  // input client.
+  void ProcessInputMethodResult(const base::NativeEvent& native_key_event,
+                                bool filtered);
+
+  // Checks if the pending input method result needs inserting into the focused
+  // text input client as a single character.
+  bool NeedInsertChar() const;
+
+  // Checks if there is pending input method result.
+  bool HasInputMethodResult() const;
+
+  // Fabricates a key event with VKEY_PROCESSKEY key code and dispatches it to
+  // the focused View.
+  void SendFakeProcessKeyEvent(bool pressed) const;
+
+  // Called when a pending key event has finished. The event will be removed
+  // from |pending_key_events_|.
+  void FinishPendingKeyEvent(PendingKeyEvent* pending_key);
+
+  // Abandons all pending key events. It usually happends when we lose keyboard
+  // focus, the text input type is changed or we are destroyed.
+  void AbandonAllPendingKeyEvents();
+
+  // Event handlers for IBusInputContext:
+  CHROMEG_CALLBACK_1(InputMethodIBus, void, OnCommitText,
+                     IBusInputContext*, IBusText*);
+  CHROMEG_CALLBACK_3(InputMethodIBus, void, OnForwardKeyEvent,
+                     IBusInputContext*, guint, guint, guint);
+  CHROMEG_CALLBACK_0(InputMethodIBus, void, OnShowPreeditText,
+                     IBusInputContext*);
+  CHROMEG_CALLBACK_3(InputMethodIBus, void, OnUpdatePreeditText,
+                     IBusInputContext*, IBusText*, guint, gboolean);
+  CHROMEG_CALLBACK_0(InputMethodIBus, void, OnHidePreeditText,
+                     IBusInputContext*);
+  CHROMEG_CALLBACK_0(InputMethodIBus, void, OnDestroy, IBusInputContext*);
+
+  // Event handlers for IBusBus:
+  CHROMEG_CALLBACK_0(InputMethodIBus, void, OnIBusConnected, IBusBus*);
+  CHROMEG_CALLBACK_0(InputMethodIBus, void, OnIBusDisconnected, IBusBus*);
+
+  // Returns the global IBusBus instance.
+  static IBusBus* GetIBus();
+
+  // Callback function for ibus_input_context_process_key_event_async().
+  static void ProcessKeyEventDone(IBusInputContext* context,
+                                  GAsyncResult* res,
+                                  PendingKeyEvent* data);
+
+  // Callback function for ibus_bus_create_input_context_async().
+  static void CreateInputContextDone(IBusBus* bus,
+                                     GAsyncResult* res,
+                                     PendingCreateICRequest* data);
+
+  // The input context for actual text input. Note that we don't have to support
+  // a "fake" IBus input context anymore since the latest Chrome for Chrome OS
+  // can handle input method hot keys (e.g. Shift+Alt) by itself.
+  IBusInputContext* context_;
+
+  // All pending key events. Note: we do not own these object, we just save
+  // pointers to these object so that we can abandon them when necessary.
+  // They will be deleted in ProcessKeyEventDone().
+  std::set<PendingKeyEvent*> pending_key_events_;
+
+  // The pending request for creating the |context_| instance. We need to keep
+  // this pointer so that we can receive or abandon the result.
+  PendingCreateICRequest* pending_create_ic_request_;
+
+  // Pending composition text generated by the current pending key event.
+  // It'll be sent to the focused text input client as soon as we receive the
+  // processing result of the pending key event.
+  CompositionText composition_;
+
+  // Pending result text generated by the current pending key event.
+  // It'll be sent to the focused text input client as soon as we receive the
+  // processing result of the pending key event.
+  string16 result_text_;
+
+  // Indicates if |context_| is focused or not.
+  bool context_focused_;
+
+  // Indicates if there is an ongoing composition text.
+  bool composing_text_;
+
+  // Indicates if the composition text is changed or deleted.
+  bool composition_changed_;
+
+  // If it's true then all input method result received before the next key
+  // event will be discarded.
+  bool suppress_next_result_;
+
+  // An object to compose a character from a sequence of key presses
+  // including dead key etc.
+  CharacterComposer character_composer_;
+
+  DISALLOW_COPY_AND_ASSIGN(InputMethodIBus);
+};
+
+}  // namespace ui
+
+#endif  // UI_BASE_IME_INPUT_METHOD_IBUS_H_

ui/base/ime/mock_input_method.cc

+// Copyright (c) 2011 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.
+
+#include "ui/base/ime/mock_input_method.h"
+
+#include "base/logging.h"
+#include "base/string16.h"
+#include "ui/base/events.h"
+#include "ui/base/glib/glib_integers.h"
+#include "ui/base/ime/input_method_delegate.h"
+#include "ui/base/ime/text_input_client.h"
+#include "ui/base/keycodes/keyboard_code_conversion.h"
+
+#if defined(USE_X11)
+#include <X11/X.h>
+#include <X11/Xlib.h>
+#include <X11/Xutil.h>
+#include "ui/base/keycodes/keyboard_code_conversion_x.h"
+#endif
+
+namespace {
+
+#if defined(USE_X11)
+guint32 EventFlagsFromXFlags(unsigned int flags) {
+  return (flags & LockMask ? ui::EF_CAPS_LOCK_DOWN : 0U) |
+      (flags & ControlMask ? ui::EF_CONTROL_DOWN : 0U) |
+      (flags & ShiftMask ? ui::EF_SHIFT_DOWN : 0U) |
+      (flags & Mod1Mask ? ui::EF_ALT_DOWN : 0U);
+}
+#endif
+
+}  // namespace
+
+namespace ui {
+
+MockInputMethod::MockInputMethod(internal::InputMethodDelegate* delegate)
+    : delegate_(NULL),
+      text_input_client_(NULL),
+      consume_next_key_(false) {
+  SetDelegate(delegate);
+}
+
+MockInputMethod::~MockInputMethod() {
+}
+
+void MockInputMethod::SetDelegate(internal::InputMethodDelegate* delegate) {
+  delegate_ = delegate;
+}
+
+void MockInputMethod::SetFocusedTextInputClient(TextInputClient* client) {
+  text_input_client_ = client;
+}
+
+TextInputClient* MockInputMethod::GetTextInputClient() const {
+  return text_input_client_;
+}
+
+void MockInputMethod::DispatchKeyEvent(const base::NativeEvent& native_event) {
+#if defined(USE_X11)
+  if (native_event->type == KeyRelease) {
+    // On key release, just dispatch it.
+    delegate_->DispatchKeyEventPostIME(native_event);
+  } else {
+    const uint32 state =
+        EventFlagsFromXFlags(reinterpret_cast<XKeyEvent*>(native_event)->state);
+    if (consume_next_key_) {
+      // Send the VKEY_PROCESSKEY RawKeyDown event.
+      SendFakeProcessKeyEvent(true, state);
+    } else {
+      // Send a RawKeyDown event first,
+      delegate_->DispatchKeyEventPostIME(native_event);
+      if (text_input_client_) {
+        // then send a Char event via ui::TextInputClient.
+        const KeyboardCode key_code = ui::KeyboardCodeFromNative(native_event);
+        uint16 ch = ui::DefaultSymbolFromXEvent(native_event);
+        if (!ch)
+          ch = ui::GetCharacterFromKeyCode(key_code, state);
+        if (ch)
+          text_input_client_->InsertChar(ch, state);
+      }
+    }
+  }
+  consume_next_key_ = false;
+#else
+  // TODO(yusukes): Support Windows.
+  delegate_->DispatchKeyEventPostIME(native_event);
+#endif
+}
+
+void MockInputMethod::Init(bool focused) {}
+void MockInputMethod::OnFocus() {}
+void MockInputMethod::OnBlur() {}
+void MockInputMethod::OnTextInputTypeChanged(const TextInputClient* client) {}
+void MockInputMethod::OnCaretBoundsChanged(const TextInputClient* client) {}
+void MockInputMethod::CancelComposition(const TextInputClient* client) {}
+
+std::string MockInputMethod::GetInputLocale() {
+  return "";
+}
+
+base::i18n::TextDirection MockInputMethod::GetInputTextDirection() {
+  return base::i18n::UNKNOWN_DIRECTION;
+}
+
+bool MockInputMethod::IsActive() {
+  return true;
+}
+
+ui::TextInputType MockInputMethod::GetTextInputType() const {
+  return ui::TEXT_INPUT_TYPE_NONE;
+}
+
+void MockInputMethod::ConsumeNextKey() {
+  consume_next_key_ = true;
+}
+
+void MockInputMethod::SendFakeProcessKeyEvent(bool pressed, int flags) const {
+  delegate_->DispatchFabricatedKeyEventPostIME(
+      pressed ? ET_KEY_PRESSED : ET_KEY_RELEASED, VKEY_PROCESSKEY, flags);
+}
+
+}  // namespace ui

ui/base/ime/mock_input_method.h

+// Copyright (c) 2011 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_BASE_IME_MOCK_INPUT_METHOD_H_
+#define UI_BASE_IME_MOCK_INPUT_METHOD_H_
+#pragma once
+
+#include "base/basictypes.h"
+#include "base/compiler_specific.h"
+#include "ui/base/ime/input_method.h"
+#include "ui/base/ui_export.h"
+
+namespace ui {
+
+class TextInputClient;
+
+// A mock InputMethod implementation for testing classes that use the
+// ui::InputMethod interface such as aura::DesktopHost.
+class UI_EXPORT MockInputMethod : public InputMethod {
+ public:
+  explicit MockInputMethod(internal::InputMethodDelegate* delegate);
+  virtual ~MockInputMethod();
+
+  // Overriden from InputMethod.
+  virtual void SetDelegate(internal::InputMethodDelegate* delegate) OVERRIDE;
+  virtual void Init(bool focused) OVERRIDE;
+  virtual void OnFocus() OVERRIDE;
+  virtual void OnBlur() OVERRIDE;
+  virtual void SetFocusedTextInputClient(TextInputClient* client) OVERRIDE;
+  virtual TextInputClient* GetTextInputClient() const OVERRIDE;
+  virtual void DispatchKeyEvent(const base::NativeEvent& native_event) OVERRIDE;
+  virtual void OnTextInputTypeChanged(const TextInputClient* client) OVERRIDE;
+  virtual void OnCaretBoundsChanged(const TextInputClient* client) OVERRIDE;
+  virtual void CancelComposition(const TextInputClient* client) OVERRIDE;
+  virtual std::string GetInputLocale() OVERRIDE;
+  virtual base::i18n::TextDirection GetInputTextDirection() OVERRIDE;
+  virtual bool IsActive() OVERRIDE;
+  virtual ui::TextInputType GetTextInputType() const OVERRIDE;
+
+  // If called, the next key press will not generate a Char event. Instead, it
+  // will generate the VKEY_PROCESSKEY RawKeyDown event.
+  void ConsumeNextKey();
+
+  // Sends VKEY_PROCESSKEY.
+  void SendFakeProcessKeyEvent(bool pressed, int flags) const;
+
+ private:
+  internal::InputMethodDelegate* delegate_;
+  TextInputClient* text_input_client_;
+  bool consume_next_key_;
+
+  DISALLOW_COPY_AND_ASSIGN(MockInputMethod);
+};
+
+}  // namespace ui
+
+#endif  // UI_BASE_IME_MOCK_INPUT_METHOD_H_

ui/base/ime/text_input_client.h

@@ -60,9 +60,15 @@ class UI_EXPORT TextInputClient {
   // TEXT_INPUT_TYPE_NONE at runtime.
   virtual ui::TextInputType GetTextInputType() const = 0;
 
-  // Returns current caret (insertion point) bounds relative to the View’s
+  // Returns current caret (insertion point) bounds relative to the screen
   // coordinates. If there is selection, then the selection bounds will be
   // returned.
+  // TODO(yusukes): Currently views::NativeTextfieldViews which implements this
+  // interface returns its view's coordinates. We should to do the following:
+  // 1) Modify NativeTextfieldViews so it returns screen coordinates.
+  // 2) Remove view-to-screen coordinates conversion code in InputMethodBridge.
+  // 3) Modify InputMethodWin. It requires a rect in toplevel window's
+  //    coordinates instead of screen.
   virtual gfx::Rect GetCaretBounds() = 0;
 
   // Returns true if there is composition text.

ui/ui.gyp

@@ -133,6 +133,14 @@
         'base/ime/composition_text.cc',
         'base/ime/composition_text.h',
         'base/ime/composition_underline.h',
+        'base/ime/input_method.h',
+        'base/ime/input_method_base.cc',
+        'base/ime/input_method_base.h',
+        'base/ime/input_method_delegate.h',
+        'base/ime/input_method_ibus.cc',
+        'base/ime/input_method_ibus.h',
+        'base/ime/mock_input_method.cc',
+        'base/ime/mock_input_method.h',
         'base/ime/text_input_client.cc',
         'base/ime/text_input_client.h',
         'base/ime/text_input_type.h',
@@ -358,6 +366,10 @@
            ],
         }, {  # use_aura!=1
           'sources!': [
+            'base/ime/input_method_ibus.cc',
+            'base/ime/input_method_ibus.h',
+            'base/ime/mock_input_method.cc',
+            'base/ime/mock_input_method.h',
             'gfx/native_theme_aura.cc',
             'gfx/native_theme_aura.h',
           ]
@@ -371,6 +383,21 @@
             ['exclude', 'gfx/path_win.cc'],
           ],
         }],
+        ['use_ibus==1', {
+          'dependencies': [
+            '../build/linux/system.gyp:ibus',
+          ],
+          'sources/': [
+            ['exclude', 'base/ime/mock_input_method.cc'],
+            ['exclude', 'base/ime/mock_input_method.h'],
+          ],
+        }, { # else: use_ibus != 1
+          'sources/': [
+            ['exclude', 'base/ime/input_method_ibus.cc'],
+            ['exclude', 'base/ime/input_method_ibus.h'],
+          ],
+        }],
+
         ['use_glib == 1', {
           'dependencies': [
             # font_gtk.cc uses fontconfig.