Notify launcher page with onTransitionChanged event

ui/app_list/app_list_view_delegate.h

 // 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.
 
 #ifndef UI_APP_LIST_APP_LIST_VIEW_DELEGATE_H_
 #define UI_APP_LIST_APP_LIST_VIEW_DELEGATE_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 39 matching lines @@
     base::string16 name;
 
     // The email address of this user.
     base::string16 email;
 
     // The path to this user's profile directory.
     base::FilePath profile_path;
   };
   typedef std::vector<User> Users;
 
-  // AppListView owns the delegate.
   virtual ~AppListViewDelegate() {}
 
   // Whether to force the use of a native desktop widget when the app list
   // window is first created.
   virtual bool ForceNativeDesktop() const = 0;
 
   // Sets the delegate to use the profile at |profile_path|. This is currently
   // only used by non-Ash Windows.
   virtual void SetProfileByPath(const base::FilePath& profile_path) = 0;
 
@@ skipping 66 matching lines @@
 
 #if defined(TOOLKIT_VIEWS)
   // Creates the web view for the start page. The caller takes the ownership of
   // the returned view.
   virtual views::View* CreateStartPageWebView(const gfx::Size& size) = 0;
 
   // Creates the web views for the user-specified custom pages. The caller takes
   // ownership of the returned views.
   virtual std::vector<views::View*> CreateCustomPageWebViews(
       const gfx::Size& size) = 0;
+
+  // Invoked when the custom launcher's animation changes.
+  virtual void CustomLauncherPageAnimationChanged(double progress) = 0;
 #endif
 
   // Returns true if the delegate supports speech recognition.
   virtual bool IsSpeechRecognitionEnabled() = 0;
 
   // Returns the list of users (for AppListMenu).
   virtual const Users& GetUsers() const = 0;
 
   // Returns true if the app list should be centered and in landscape mode.
   virtual bool ShouldCenterWindow() const = 0;
 
   // Adds/removes an observer for profile changes.
   virtual void AddObserver(AppListViewDelegateObserver* observer) {}
   virtual void RemoveObserver(AppListViewDelegateObserver* observer) {}
 };
 
 }  // namespace app_list
 
 #endif  // UI_APP_LIST_APP_LIST_VIEW_DELEGATE_H_