Fix crash-on-invalid where a ParenListExpr shows up as a message receiver
while trying to do error recovery.

rdar://13207886

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@175282 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaExprObjC.cpp b/lib/Sema/SemaExprObjC.cpp
index 7f0c832..76ee983 100644
--- a/lib/Sema/SemaExprObjC.cpp
+++ b/lib/Sema/SemaExprObjC.cpp
@@ -2485,6 +2485,13 @@
                                       MultiExprArg Args) {
   if (!Receiver)
     return ExprError();
+
+  // A ParenListExpr can show up while doing error recovery with invalid code.
+  if (isa<ParenListExpr>(Receiver)) {
+    ExprResult Result = MaybeConvertParenListExprToParenExpr(S, Receiver);
+    if (Result.isInvalid()) return ExprError();
+    Receiver = Result.take();
+  }
   
   if (RespondsToSelectorSel.isNull()) {
     IdentifierInfo *SelectorId = &Context.Idents.get("respondsToSelector");