Allow scroll events to open custom launcher pages.

ui/app_list/views/app_list_view.cc

Index: ui/app_list/views/app_list_view.cc
diff --git a/ui/app_list/views/app_list_view.cc b/ui/app_list/views/app_list_view.cc
index f2083749f9ab8f7652ca6e3123777a8f1a78193e..00f83a911c77f27fd908f933d61606939168209f 100644
--- a/ui/app_list/views/app_list_view.cc
+++ b/ui/app_list/views/app_list_view.cc
@@ -338,6 +338,19 @@ bool AppListView::ShouldHandleSystemCommands() const {
   return true;
 }
 
+bool AppListView::ShouldDescendIntoChildForEventHandling(
+    gfx::NativeView child,
+    const gfx::Point& location) {
+  // While on the start page, don't descend into the custom launcher page. Since
+  // the only valid action is to open it.
+  ContentsView* contents_view = app_list_main_view_->contents_view();
+  if (contents_view->GetActiveState() == AppListModel::STATE_START)
+    return !contents_view->GetCustomPageCollapsedBounds().Contains(location);
+
+  return views::BubbleDelegateView::ShouldDescendIntoChildForEventHandling(
+      child, location);
+}
+
 void AppListView::Prerender() {
   app_list_main_view_->Prerender();
 }
@@ -434,8 +447,6 @@ void AppListView::InitContents(gfx::NativeView parent, int initial_apps_page) {
 void AppListView::InitChildWidgets() {
   DCHECK(search_box_view_);
 
-  app_list_main_view_->InitWidgets();
-
   // Create the search box widget.
   views::Widget::InitParams search_box_widget_params(
       views::Widget::InitParams::TYPE_CONTROL);