views: Add optional overlay image to ImageButton

ui/views/controls/button/image_button.cc

-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// 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/animation/throb_animation.h"
 #include "ui/gfx/canvas.h"
 #include "ui/gfx/skbitmap_operations.h"
 
@@ skipping 29 matching lines @@
                                 const SkBitmap* mask) {
   if (!image || !mask) {
     background_image_.reset();
     return;
   }
 
   background_image_ =
       SkBitmapOperations::CreateButtonBackground(color, *image, *mask);
 }
 
+void ImageButton::SetOverlayImage(const SkBitmap* image) {
+  if (!image) {
+    overlay_image_.reset();
+    return;
+  }
+  overlay_image_ = *image;
+}
+
 void ImageButton::SetImageAlignment(HorizontalAlignment h_align,
                                     VerticalAlignment v_align) {
   h_alignment_ = h_align;
   v_alignment_ = v_align;
   SchedulePaint();
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 // ImageButton, View overrides:
 
@@ skipping 17 matching lines @@
     else if (h_alignment_ == ALIGN_RIGHT)
       x = width() - img.width();
 
     if (v_alignment_ == ALIGN_MIDDLE)
       y = (height() - img.height()) / 2;
     else if (v_alignment_ == ALIGN_BOTTOM)
       y = height() - img.height();
 
     if (!background_image_.empty())
       canvas->DrawBitmapInt(background_image_, x, y);
+
     canvas->DrawBitmapInt(img, x, y);
+
+    if (!overlay_image_.empty())
+      canvas->DrawBitmapInt(overlay_image_, x, y);
   }
   OnPaintFocusBorder(canvas);
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 // ImageButton, protected:
 
 SkBitmap ImageButton::GetImageToPaint() {
   SkBitmap img;
 
@@ skipping 66 matching lines @@
 bool ToggleImageButton::GetTooltipText(const gfx::Point& p,
                                        string16* tooltip) const {
   if (!toggled_ || toggled_tooltip_text_.empty())
     return Button::GetTooltipText(p, tooltip);
 
   *tooltip = toggled_tooltip_text_;
   return true;
 }
 
 }  // namespace views