Fix error in tablegen when either operand of !if is an empty list.

!if([Something], []) would error with "No type for list".

llvm-svn: 210572
diff --git a/llvm/lib/TableGen/TGParser.h b/llvm/lib/TableGen/TGParser.h
index 6fd442a..9f4b7e9 100644
--- a/llvm/lib/TableGen/TGParser.h
+++ b/llvm/lib/TableGen/TGParser.h
@@ -181,7 +181,7 @@
   std::vector<unsigned> ParseRangeList();
   bool ParseRangePiece(std::vector<unsigned> &Ranges);
   RecTy *ParseType();
-  Init *ParseOperation(Record *CurRec);
+  Init *ParseOperation(Record *CurRec, RecTy *ItemType);
   RecTy *ParseOperatorType();
   Init *ParseObjectName(MultiClass *CurMultiClass);
   Record *ParseClassID();