MacViews: draw combobox arrow backgrounds

ui/native_theme/native_theme_base.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/native_theme/native_theme_base.h"
 
 #include <limits>
 
 #include "base/command_line.h"
 #include "base/logging.h"
@@ skipping 182 matching lines @@
     return;
 
   canvas->save();
   canvas->clipRect(gfx::RectToSkRect(rect));
 
   switch (part) {
     // Please keep these in the order of NativeTheme::Part.
     case kComboboxArrow:
       CommonThemePaintComboboxArrow(canvas, rect);
       break;
+    case kComboboxArrowBackground:
+      PaintComboboxArrowBackground(canvas, state, rect);
+      break;
     case kCheckbox:
       PaintCheckbox(canvas, state, rect, extra.button);
       break;
     case kInnerSpinButton:
       PaintInnerSpinButton(canvas, state, rect, extra.inner_spin);
       break;
     case kMenuList:
       PaintMenuList(canvas, state, rect, extra.menu_list);
       break;
     case kMenuPopupBackground:
@@ skipping 820 matching lines @@
   SkScalar min_diff = Clamp((hsv1[1] + hsv2[1]) * 1.2f, 0.28f, 0.5f);
   SkScalar diff = Clamp(fabs(hsv1[2] - hsv2[2]) / 2, min_diff, 0.5f);
 
   if (hsv1[2] + hsv2[2] > 1.0)
     diff = -diff;
 
   return SaturateAndBrighten(hsv2, -0.2f, diff);
 }
 
 }  // namespace ui