Update shelf spacing in Chrome OS according to the MD specs

chrome/browser/ui/apps/chrome_app_delegate.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 "chrome/browser/ui/apps/chrome_app_delegate.h"
 
 #include <memory>
 #include <utility>
 
 #include "base/macros.h"
@@ skipping 264 matching lines @@
     const GURL& security_origin,
     content::MediaStreamType type,
     const extensions::Extension* extension) {
   return MediaCaptureDevicesDispatcher::GetInstance()
       ->CheckMediaAccessPermission(
           web_contents, security_origin, type, extension);
 }
 
 int ChromeAppDelegate::PreferredIconSize() {
 #if defined(USE_ASH)
-  return ash::kShelfSize;
+  return ash::GetShelfConstant(ash::SHELF_SIZE);
 #else
   return extension_misc::EXTENSION_ICON_SMALL;
 #endif
 }
 
 void ChromeAppDelegate::SetWebContentsBlocked(
     content::WebContents* web_contents,
     bool blocked) {
   if (!blocked)
     web_contents->Focus();
@@ skipping 42 matching lines @@
                                 const content::NotificationDetails& details) {
   switch (type) {
     case chrome::NOTIFICATION_APP_TERMINATING:
       if (!terminating_callback_.is_null())
         terminating_callback_.Run();
       break;
     default:
       NOTREACHED() << "Received unexpected notification";
   }
 }