API changes to match llvm ToT.

llvm-svn: 79868
diff --git a/clang/lib/Frontend/InitPreprocessor.cpp b/clang/lib/Frontend/InitPreprocessor.cpp
index 877c788..466cbaf 100644
--- a/clang/lib/Frontend/InitPreprocessor.cpp
+++ b/clang/lib/Frontend/InitPreprocessor.cpp
@@ -78,7 +78,7 @@
     
   // Escape double quotes etc.
   Buf.push_back('"');
-  std::string EscapedFile = Lexer::Stringify(Path.toString());
+  std::string EscapedFile = Lexer::Stringify(Path.str());
   Buf.insert(Buf.end(), EscapedFile.begin(), EscapedFile.end());
   Buf.push_back('"');
 }