Improve layout for bookmark-apps. Add a treatment for small icons.

chrome/browser/ui/webui/extension_icon_source.h

 // Copyright (c) 2011 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.
 
 #ifndef CHROME_BROWSER_UI_WEBUI_EXTENSION_ICON_SOURCE_H_
 #define CHROME_BROWSER_UI_WEBUI_EXTENSION_ICON_SOURCE_H_
 #pragma once
 
 #include <string>
 
@@ skipping 39 matching lines @@
 //  3) The default extension / application icon if there are still no matches.
 //
 class ExtensionIconSource : public ChromeURLDataManager::DataSource,
                             public ImageLoadingTracker::Observer {
  public:
   explicit ExtensionIconSource(Profile* profile);
   virtual ~ExtensionIconSource();
 
   // Gets the URL of the |extension| icon in the given |size|, falling back
   // based on the |match| type. If |grayscale|, the URL will be for the
-  // desaturated version of the icon.
+  // desaturated version of the icon. |exists|, if non-NULL, will be set to true
+  // if the icon exists; false if it will lead to a default or not-present
+  // image.
   static GURL GetIconURL(const Extension* extension,
                          Extension::Icons icon_size,
                          ExtensionIconSet::MatchType match,
-                         bool grayscale);
+                         bool grayscale,
+                         bool* exists);
 
   // A public utility function for accessing the bitmap of the image specified
   // by |resource_id|.
   static SkBitmap* LoadImageByResourceId(int resource_id);
 
   // ChromeURLDataManager::DataSource
 
   virtual std::string GetMimeType(const std::string&) const;
 
   virtual void StartDataRequest(const std::string& path,
@@ skipping 80 matching lines @@
   scoped_ptr<SkBitmap> default_app_data_;
 
   scoped_ptr<SkBitmap> default_extension_data_;
 
   CancelableRequestConsumerT<int, 0> cancelable_consumer_;
 
   DISALLOW_COPY_AND_ASSIGN(ExtensionIconSource);
 };
 
 #endif  // CHROME_BROWSER_UI_WEBUI_EXTENSION_ICON_SOURCE_H_