Enable overloading of OpenCL events - this is needed for the overloaded OpenCL builtin functions.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@174630 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaExprCXX.cpp b/lib/Sema/SemaExprCXX.cpp
index c70041b..7f24af8 100644
--- a/lib/Sema/SemaExprCXX.cpp
+++ b/lib/Sema/SemaExprCXX.cpp
@@ -2783,6 +2783,12 @@
     break;
   }
 
+  case ICK_Zero_Event_Conversion:
+    From = ImpCastExprToType(From, ToType,
+                             CK_ZeroToOCLEvent,
+                             From->getValueKind()).take();
+    break;
+
   case ICK_Lvalue_To_Rvalue:
   case ICK_Array_To_Pointer:
   case ICK_Function_To_Pointer: