Add a card background to the app list search result groups.

ui/app_list/views/tile_item_view.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/views/tile_item_view.h"
 
 #include "ui/app_list/app_list_constants.h"
 #include "ui/app_list/views/app_list_main_view.h"
 #include "ui/views/background.h"
 #include "ui/views/controls/image_view.h"
@@ skipping 17 matching lines @@
       views::BoxLayout::kVertical, kTileHorizontalPadding, 0, 0);
   layout_manager->set_main_axis_alignment(
       views::BoxLayout::MAIN_AXIS_ALIGNMENT_CENTER);
   SetLayoutManager(layout_manager);
 
   icon_->SetImageSize(gfx::Size(kTileIconSize, kTileIconSize));
 
   ui::ResourceBundle& rb = ui::ResourceBundle::GetSharedInstance();
   title_->SetAutoColorReadabilityEnabled(false);
   title_->SetEnabledColor(kGridTitleColor);
-  title_->set_background(views::Background::CreateSolidBackground(
-      kLabelBackgroundColor));
   title_->SetFontList(rb.GetFontList(kItemTextFontStyle));
   title_->SetHorizontalAlignment(gfx::ALIGN_CENTER);
 
   AddChildView(icon_);
   AddChildView(title_);
 }
 
 TileItemView::~TileItemView() {
 }
 
+void TileItemView::SetTitleBackgroundColor(SkColor color) {
+  title_->set_background(views::Background::CreateSolidBackground(color));
+}
+
 void TileItemView::SetIcon(const gfx::ImageSkia& icon) {
   icon_->SetImage(icon);
 }
 
 void TileItemView::SetTitle(const base::string16& title) {
   title_->SetText(title);
 }
 
 gfx::Size TileItemView::GetPreferredSize() const {
   return gfx::Size(kTileSize, kTileSize);
 }
 
 }  // namespace app_list