Notify launcher page with onTransitionChanged event

ui/app_list/views/contents_view.cc

Index: ui/app_list/views/contents_view.cc
diff --git a/ui/app_list/views/contents_view.cc b/ui/app_list/views/contents_view.cc
index c9ea27655c55962d62d45ed9a73f2db58491bcb9..a44cd1439f4dcaf7ab2602aa7edc40f16e13ffb9 100644
--- a/ui/app_list/views/contents_view.cc
+++ b/ui/app_list/views/contents_view.cc
@@ -56,7 +56,14 @@ void ContentsView::Init(AppListModel* model,
              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);
@@ -137,6 +144,15 @@ int ContentsView::GetPageIndexForState(AppListModel::State state) const {
   return it->second;
 }
 
+AppListModel::State ContentsView::GetStateForPageIndex(int index) const {
+  std::map<int, AppListModel::State>::const_iterator it =
+      view_to_state_.find(index);
+  if (it == view_to_state_.end())
+    return AppListModel::INVALID_STATE;
+
+  return it->second;
+}
+
 int ContentsView::NumLauncherPages() const {
   return pagination_model_.total_pages();
 }