Refactors the auto-launch logic and adds tests for it.

ui/app_list/views/search_result_view_delegate.h

Index: ui/app_list/views/search_result_view_delegate.h
diff --git a/ui/app_list/views/search_result_view_delegate.h b/ui/app_list/views/search_result_view_delegate.h
index e86ccc89c99f8fa858411183df946cfd33bfc05e..5681c27406049f87319e9be3c79db443b7ce984d 100644
--- a/ui/app_list/views/search_result_view_delegate.h
+++ b/ui/app_list/views/search_result_view_delegate.h
@@ -5,11 +5,13 @@
 #ifndef UI_APP_LIST_VIEWS_SEARCH_RESULT_VIEW_DELEGATE_H_
 #define UI_APP_LIST_VIEWS_SEARCH_RESULT_VIEW_DELEGATE_H_
 
+#include "ui/app_list/app_list_export.h"
+
 namespace app_list {
 
 class SearchResultView;
 
-class SearchResultViewDelegate {
+class APP_LIST_EXPORT SearchResultViewDelegate {
  public:
   // Called when the search result is activated.
   virtual void SearchResultActivated(SearchResultView* view,