[C++11] Add 'override' keyword to virtual methods that override their base class.

llvm-svn: 203641
diff --git a/clang/lib/Parse/ParseAST.cpp b/clang/lib/Parse/ParseAST.cpp
index 0079aae..0f5a1b3 100644
--- a/clang/lib/Parse/ParseAST.cpp
+++ b/clang/lib/Parse/ParseAST.cpp
@@ -36,7 +36,7 @@
   const Parser &P;
 public:
   PrettyStackTraceParserEntry(const Parser &p) : P(p) {}
-  virtual void print(raw_ostream &OS) const;
+  void print(raw_ostream &OS) const override;
 };
 
 /// If a crash happens while the parser is active, print out a line indicating