Cleanup: remove NotifyAccessibilityEvent from views::Widget.

ui/views/controls/button/image_button.cc

 // Copyright (c) 2012 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/views/controls/button/image_button.h"
 
 #include "base/utf_string_conversions.h"
 #include "ui/base/accessibility/accessible_view_state.h"
 #include "ui/base/animation/throb_animation.h"
 #include "ui/gfx/canvas.h"
@@ skipping 147 matching lines @@
     return;
 
   for (int i = 0; i < STATE_COUNT; ++i) {
     gfx::ImageSkia temp = images_[i];
     images_[i] = alternate_images_[i];
     alternate_images_[i] = temp;
   }
   toggled_ = toggled;
   SchedulePaint();
 
-  GetWidget()->NotifyAccessibilityEvent(
-      this, ui::AccessibilityTypes::EVENT_VALUE_CHANGED, true);
+  NotifyAccessibilityEvent(ui::AccessibilityTypes::EVENT_VALUE_CHANGED, true);
 }
 
 void ToggleImageButton::SetToggledImage(ButtonState state,
                                         const gfx::ImageSkia* image) {
   if (toggled_) {
     images_[state] = image ? *image : gfx::ImageSkia();
     if (state_ == state)
       SchedulePaint();
   } else {
     alternate_images_[state] = image ? *image : gfx::ImageSkia();
@@ skipping 36 matching lines @@
   *tooltip = toggled_tooltip_text_;
   return true;
 }
 
 void ToggleImageButton::GetAccessibleState(ui::AccessibleViewState* state) {
   ImageButton::GetAccessibleState(state);
   GetTooltipText(gfx::Point(), &state->name);
 }
 
 }  // namespace views