Apply review comment from Jordan Rose.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@157387 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/clang/Tooling/Refactoring.h b/include/clang/Tooling/Refactoring.h
index 36b8446..56509a6 100644
--- a/include/clang/Tooling/Refactoring.h
+++ b/include/clang/Tooling/Refactoring.h
@@ -68,7 +68,7 @@
 
   /// \brief Accessors.
   /// @{
-  std::string getFilePath() const { return FilePath; }
+  StringRef getFilePath() const { return FilePath; }
   unsigned getOffset() const { return Offset; }
   unsigned getLength() const { return Length; }
   /// @}