Remove ImageSkia::empty and ImageSkia::extractSubset

ash/launcher/tabbed_launcher_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 "ash/launcher/tabbed_launcher_button.h"
 
 #include <algorithm>
 
 #include "ash/launcher/launcher_button_host.h"
 #include "ash/launcher/launcher_types.h"
@@ skipping 40 matching lines @@
   animating_image_ = SkBitmap();
 }
 
 void TabbedLauncherButton::IconView::AnimationProgressed(
     const ui::Animation* animation) {
   if (animation_->current_part_index() == 1)
     SchedulePaint();
 }
 
 void TabbedLauncherButton::IconView::SetTabImage(const gfx::ImageSkia& image) {
-  if (image.empty()) {
-    if (!image_.empty()) {
+  if (image.isNull()) {
+    if (!image_.isNull()) {
       // Pause for 500ms, then ease out for 200ms.
       ui::MultiAnimation::Parts animation_parts;
       animation_parts.push_back(ui::MultiAnimation::Part(500, ui::Tween::ZERO));
       animation_parts.push_back(
           ui::MultiAnimation::Part(200, ui::Tween::EASE_OUT));
       animation_.reset(new ui::MultiAnimation(animation_parts));
       animation_->set_continuous(false);
       animation_->set_delegate(this);
       animation_->Start();
       animating_image_ = image_;
@@ skipping 62 matching lines @@
   state->role = ui::AccessibilityTypes::ROLE_PUSHBUTTON;
   state->name = host()->GetAccessibleName(this);
 }
 
 LauncherButton::IconView* TabbedLauncherButton::CreateIconView() {
   return new IconView(this);
 }
 
 }  // namespace internal
 }  // namespace ash