Use app list item shadow for app list folders.

ui/app_list/folder_image.cc

 // Copyright 2014 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/app_list/folder_image.h"
 
 #include <vector>
 
 #include "ui/app_list/app_list_constants.h"
 #include "ui/app_list/app_list_item.h"
@@ skipping 59 matching lines @@
   if (icon.isNull())
     return;
 
   gfx::ImageSkia resized(gfx::ImageSkiaOperations::CreateResizedImage(
       icon, skia::ImageOperations::RESIZE_BEST, icon_size));
   canvas->DrawImageInt(resized, 0, 0, resized.width(), resized.height(), x, y,
                        resized.width(), resized.height(), true);
 }
 
 void FolderImageSource::Draw(gfx::Canvas* canvas) {
-  // Draw circle for folder shadow.
-  gfx::PointF shadow_center(size().width() / 2, size().height() / 2);
   SkPaint paint;
+  // Draw circle for folder bubble.
+  gfx::PointF bubble_center(size().width() / 2, size().height() / 2);
+  bubble_center.Offset(0, -kFolderBubbleOffsetY);
   paint.setStyle(SkPaint::kFill_Style);
   paint.setAntiAlias(true);
-  paint.setColor(kFolderShadowColor);
-  canvas->sk_canvas()->drawCircle(shadow_center.x(), shadow_center.y(),
-                                  kFolderShadowRadius, paint);
-  // Draw circle for folder bubble.
-  gfx::PointF bubble_center(shadow_center);
-  bubble_center.Offset(0, -kFolderShadowOffsetY);
   paint.setColor(kFolderBubbleColor);
   canvas->sk_canvas()->drawCircle(bubble_center.x(), bubble_center.y(),
                                   kFolderBubbleRadius, paint);
 
   if (icons_.size() == 0)
     return;
 
   // Draw top items' icons.
   const gfx::Size item_icon_size(ItemIconSize());
   std::vector<gfx::Rect> top_icon_bounds =
@@ skipping 122 matching lines @@
     top_icons.push_back(item->icon());
 
   const gfx::Size icon_size = gfx::Size(kGridIconDimension, kGridIconDimension);
   icon_ =
       gfx::ImageSkia(new FolderImageSource(top_icons, icon_size), icon_size);
 
   FOR_EACH_OBSERVER(FolderImageObserver, observers_, OnFolderImageUpdated());
 }
 
 }  // namespace app_list