Notify launcher page with onTransitionChanged event

ui/app_list/views/contents_view.cc

 // 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.
 
 #include "ui/app_list/views/contents_view.h"
 
 #include <algorithm>
 #include <vector>
 
 #include "base/logging.h"
@@ skipping 38 matching lines @@
                         AppListViewDelegate* view_delegate) {
   DCHECK(model);
 
   if (app_list::switches::IsExperimentalAppListEnabled()) {
     std::vector<views::View*> custom_page_views =
         view_delegate->CreateCustomPageWebViews(GetLocalBounds().size());
     for (std::vector<views::View*>::const_iterator it =
              custom_page_views.begin();
          it != custom_page_views.end();
          ++it) {
-      AddLauncherPage(*it, IDR_APP_LIST_NOTIFICATIONS_ICON);
+      // Only the first launcher page should be the custom launcher page state.
+      if (it == custom_page_views.begin()) {
+        AddLauncherPage(*it,
+                        IDR_APP_LIST_NOTIFICATIONS_ICON,
+                        AppListModel::STATE_CUSTOM_LAUNCHER_PAGE);
+      } else {
+        AddLauncherPage(*it, IDR_APP_LIST_NOTIFICATIONS_ICON);
+      }
     }
 
     start_page_view_ = new StartPageView(app_list_main_view_, view_delegate);
     AddLauncherPage(
         start_page_view_, IDR_APP_LIST_SEARCH_ICON, AppListModel::STATE_START);
   } else {
     search_results_view_ =
         new SearchResultListView(app_list_main_view_, view_delegate);
     AddLauncherPage(
         search_results_view_, 0, AppListModel::STATE_SEARCH_RESULTS);
@@ skipping 287 matching lines @@
 }
 
 void ContentsView::TransitionStarted() {
 }
 
 void ContentsView::TransitionChanged() {
   UpdatePageBounds();
 }
 
 }  // namespace app_list