Update Clang for 3.5 rebase (r209713).

Change-Id: I8c9133b0f8f776dc915f270b60f94962e771bc83
diff --git a/lib/Edit/EditedSource.cpp b/lib/Edit/EditedSource.cpp
index 8fa2ee5..6cf6335 100644
--- a/lib/Edit/EditedSource.cpp
+++ b/lib/Edit/EditedSource.cpp
@@ -158,7 +158,7 @@
   }
 
   FileOffset TopBegin, TopEnd;
-  FileEdit *TopFA = 0;
+  FileEdit *TopFA = nullptr;
 
   if (I == FileEdits.end()) {
     FileEditsTy::iterator