Allow app list tiles to show search results in the experimental app list.

ui/app_list/search_result.cc

Index: ui/app_list/search_result.cc
diff --git a/ui/app_list/search_result.cc b/ui/app_list/search_result.cc
index bfa1da9b6a7dfc10fb9ce2256c654243ebd04032..653d08950d9a81911a5b4e2f8560c3ad6b518ff2 100644
--- a/ui/app_list/search_result.cc
+++ b/ui/app_list/search_result.cc
@@ -32,7 +32,9 @@ SearchResult::SearchResult()
       percent_downloaded_(0) {
 }
 
-SearchResult::~SearchResult() {}
+SearchResult::~SearchResult() {
+  FOR_EACH_OBSERVER(SearchResultObserver, observers_, OnResultDestroying());
+}
 
 void SearchResult::SetIcon(const gfx::ImageSkia& icon) {
   icon_ = icon;