ash: Add support for additional icons in apps search list.

ui/app_list/search_result_list_view_delegate.h

Index: ui/app_list/search_result_list_view_delegate.h
diff --git a/ui/app_list/search_result_list_view_delegate.h b/ui/app_list/search_result_list_view_delegate.h
index 419bb3e2b2f10c0f7526f7309c3818a44c26cdeb..3022e3f41a8c6eaaddc2935e01f8367eac9a762a 100644
--- a/ui/app_list/search_result_list_view_delegate.h
+++ b/ui/app_list/search_result_list_view_delegate.h
@@ -19,6 +19,12 @@ class APP_LIST_EXPORT SearchResultListViewDelegate {
   virtual void OpenResult(const SearchResult& result,
                           int event_flags) = 0;
 
+  // Called to invoke a custom action on |result|.  |action_index| corresponds
+  // to the index of the icon in |result.action_icons()| that was activated.
+  virtual void InvokeResultAction(const SearchResult& result,
+                                  int action_index,
+                                  int event_flags) = 0;
+
  protected:
   virtual ~SearchResultListViewDelegate() {}
 };