Update LLVM for 3.5 rebase (r209712).

Change-Id: I149556c940fb7dc92d075273c87ff584f400941f
diff --git a/lib/ExecutionEngine/Interpreter/Interpreter.cpp b/lib/ExecutionEngine/Interpreter/Interpreter.cpp
index 6d4f6f7..c589457 100644
--- a/lib/ExecutionEngine/Interpreter/Interpreter.cpp
+++ b/lib/ExecutionEngine/Interpreter/Interpreter.cpp
@@ -38,7 +38,7 @@
     if (ErrStr)
       *ErrStr = EC.message();
     // We got an error, just return 0
-    return 0;
+    return nullptr;
   }
 
   return new Interpreter(M);