Update Clang for 3.5 rebase (r209713).

Change-Id: I8c9133b0f8f776dc915f270b60f94962e771bc83
diff --git a/lib/Frontend/DependencyFile.cpp b/lib/Frontend/DependencyFile.cpp
index b472eaa..e72be89 100644
--- a/lib/Frontend/DependencyFile.cpp
+++ b/lib/Frontend/DependencyFile.cpp
@@ -96,7 +96,7 @@
 
   if (Opts.Targets.empty()) {
     PP.getDiagnostics().Report(diag::err_fe_dependency_file_requires_MT);
-    return NULL;
+    return nullptr;
   }
 
   // Disable the "file not found" diagnostic if the -MG option was given.
@@ -141,7 +141,7 @@
 
   const FileEntry *FE =
     SM.getFileEntryForID(SM.getFileID(SM.getExpansionLoc(Loc)));
-  if (FE == 0) return;
+  if (!FE) return;
 
   StringRef Filename = FE->getName();
   if (!FileMatchesDepCriteria(Filename.data(), FileType))