Refactor Select-to-speak so that mouse events are forwarded to the extension.

chrome/browser/chromeos/accessibility/select_to_speak_event_handler.h

 // Copyright 2016 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 CHROME_BROWSER_CHROMEOS_ACCESSIBILITY_SELECT_TO_SPEAK_EVENT_HANDLER_H_
 #define CHROME_BROWSER_CHROMEOS_ACCESSIBILITY_SELECT_TO_SPEAK_EVENT_HANDLER_H_
 
 #include <set>
 
 #include "base/macros.h"
 #include "ui/events/event_handler.h"
 #include "ui/events/keycodes/keyboard_codes.h"
 
 namespace chromeos {
 
+class SelectToSpeakForwardedEventDelegateForTesting {
+ public:
+  virtual void OnForwardEventToSelectToSpeakExtension(
+      const ui::MouseEvent& event) = 0;
+};
+
 // Intercepts mouse events while the Search key is held down, and sends
 // accessibility events to the Select-to-speak extension instead.
 class SelectToSpeakEventHandler : public ui::EventHandler {
  public:
   SelectToSpeakEventHandler();
   ~SelectToSpeakEventHandler() override;
 
+  // For testing, call the provided callback with any events that would have
+  // been forwarded to the Select-to-speak extension instead.
+  void CaptureForwardedEventsForTesting(
+      SelectToSpeakForwardedEventDelegateForTesting* delegate);
+
  private:
   // EventHandler:
   void OnKeyEvent(ui::KeyEvent* event) override;
   void OnMouseEvent(ui::MouseEvent* event) override;
 
   void CancelEvent(ui::Event* event);
   void SendCancelAXEvent();
 
   enum State {
     // Neither the Search key nor the mouse button are down.
@@ skipping 22 matching lines @@
 
   State state_ = INACTIVE;
 
   // The set of keys that are currently down. Updated whenever a key is
   // pressed or released.
   std::set<ui::KeyboardCode> keys_currently_down_;
   // The set of keys that have been pressed together. Updated whenever a key
   // is pressed, and only cleared when all keys are released.
   std::set<ui::KeyboardCode> keys_pressed_together_;
 
+  SelectToSpeakForwardedEventDelegateForTesting* event_delegate_for_testing_;
+
   DISALLOW_COPY_AND_ASSIGN(SelectToSpeakEventHandler);
 };
 
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_CHROMEOS_ACCESSIBILITY_SELECT_TO_SPEAK_EVENT_HANDLER_H_