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

llvm-svn: 203758
diff --git a/clang/lib/Frontend/CacheTokens.cpp b/clang/lib/Frontend/CacheTokens.cpp
index 5cb364e..0fca513 100644
--- a/clang/lib/Frontend/CacheTokens.cpp
+++ b/clang/lib/Frontend/CacheTokens.cpp
@@ -516,7 +516,7 @@
   ~StatListener() {}
 
   LookupResult getStat(const char *Path, FileData &Data, bool isFile,
-                       vfs::File **F, vfs::FileSystem &FS) {
+                       vfs::File **F, vfs::FileSystem &FS) override {
     LookupResult Result = statChained(Path, Data, isFile, F, FS);
 
     if (Result == CacheMissing) // Failed 'stat'.