Avoiding voice search crash if none of search providers returned anything.

ui/app_list/views/search_result_list_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/search_result_list_view.h"
 
 #include <algorithm>
 #include <vector>
 
 #include "base/bind.h"
@@ skipping 205 matching lines @@
 void SearchResultListView::VisibilityChanged(views::View* starting_from,
                                              bool is_visible) {
   if (is_visible)
     UpdateAutoLaunchState();
   else
     CancelAutoLaunchTimeout();
 }
 
 void SearchResultListView::AnimationEnded(const gfx::Animation* animation) {
   DCHECK_EQ(auto_launch_animation_.get(), animation);
-  view_delegate_->OpenSearchResult(results()->GetItemAt(0), true, ui::EF_NONE);
+  if (results()->item_count() > 0) {
+    view_delegate_->OpenSearchResult(results()->GetItemAt(0), true,
+                                     ui::EF_NONE);
+  }
 
   // The auto-launch has to be canceled explicitly. Think that one of searcher
   // is extremely slow. Sometimes the events would happen in the following
   // order:
   //  1. The search results arrive, auto-launch is dispatched
   //  2. Timed out and auto-launch the first search result
   //  3. Then another searcher adds search results more
   // At the step 3, we shouldn't dispatch the auto-launch again.
   CancelAutoLaunchTimeout();
 }
@@ skipping 20 matching lines @@
         view->result(), action_index, event_flags);
   }
 }
 
 void SearchResultListView::OnSearchResultInstalled(SearchResultView* view) {
   if (delegate_ && view->result())
     delegate_->OnResultInstalled(view->result());
 }
 
 }  // namespace app_list