Implement chrome.input.ime.setComposition/commitText API.

ui/base/ime/input_method_base.h

Index: ui/base/ime/input_method_base.h
diff --git a/ui/base/ime/input_method_base.h b/ui/base/ime/input_method_base.h
index 432a80f2ab2e3922c1c30a914fe7531ddc85525d..c06e34422311420c11def6e659d5c2be28ab6834 100644
--- a/ui/base/ime/input_method_base.h
+++ b/ui/base/ime/input_method_base.h
@@ -11,6 +11,7 @@
 #include "base/macros.h"
 #include "base/memory/weak_ptr.h"
 #include "base/observer_list.h"
+#include "ui/base/ime/ime_input_context_handler_interface.h"
 #include "ui/base/ime/input_method.h"
 #include "ui/base/ime/ui_base_ime_export.h"
 #include "ui/events/event_dispatcher.h"
@@ -29,7 +30,8 @@ class TextInputClient;
 // implementations.
 class UI_BASE_IME_EXPORT InputMethodBase
     : NON_EXPORTED_BASE(public InputMethod),
-      public base::SupportsWeakPtr<InputMethodBase> {
+      public base::SupportsWeakPtr<InputMethodBase>,
+      public IMEInputContextHandlerInterface {
  public:
   InputMethodBase();
   ~InputMethodBase() override;
@@ -61,6 +63,17 @@ class UI_BASE_IME_EXPORT InputMethodBase
   virtual void OnDidChangeFocusedClient(TextInputClient* focused_before,
                                         TextInputClient* focused) {}
 
+  // IMEInputContextHandlerInterface:
+  void CommitText(const std::string& text) override;
+  void UpdateCompositionText(const CompositionText& text,
+                             uint32_t cursor_pos,
+                             bool visible) override;
+  void DeleteSurroundingText(int32_t offset, uint32_t length) override;
+
+  // Sends a fake key event for IME composing without physical key events.
+  // Returns true if the faked key event is stopped propagation.
+  bool SendFakeProcessKeyEvent(bool pressed) const;
+
   // Returns true if |client| is currently focused.
   bool IsTextInputClientFocused(const TextInputClient* client);
 
@@ -89,6 +102,10 @@ class UI_BASE_IME_EXPORT InputMethodBase
   // Gets the bounds of the composition text or cursor in |client|.
   std::vector<gfx::Rect> GetCompositionBounds(const TextInputClient* client);
 
+  // Indicates whether the IME extension is currently handling a physical key
+  // event. This is used in CommitText/UpdateCompositionText/etc.
+  bool handling_key_event_;

[Shu Chen, 2016/02/03 09:22:29]

Can this be moved to InputMethodEngineBase?

[Shu Chen, 2016/02/03 10:05:41]

Per offline discussion, let improve the code structure a little bit:
InputImeKeyEventHandledFunction::Run() should NOT directly call
InputImeEventRouterBase::OnKeyEventHandled(), instead, it should call
InputMethodEngineBase::KeyEventHandled() method (newly created method), which
bridges the call to InputImeEventRouterBase::OnKeyEventHandled().
In this way, |handling_key_event_| can be moved to InputMethodEngineBase:
 - InputMethodEngineBase::ProcessKeyEvent(): |handling_key_event_| = true;
 - InputMethodEngineBase::KeyEventHandled(): |handling_key_event_| = false;
 - InputMethodEngineBase::CommitText()/etc.: check |handling_key_event_| as
appropriate.

This solution will minimize the impact to ui/base/ime, thus reduce the risk.

Thanks!

+
  private:
   void SetFocusedTextInputClientInternal(TextInputClient* client);