Remove unused include of VectorExtras.h.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@147737 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/utils/TableGen/ClangDiagnosticsEmitter.cpp b/utils/TableGen/ClangDiagnosticsEmitter.cpp
index 4435fa7..8240360 100644
--- a/utils/TableGen/ClangDiagnosticsEmitter.cpp
+++ b/utils/TableGen/ClangDiagnosticsEmitter.cpp
@@ -18,7 +18,6 @@
 #include "llvm/ADT/DenseSet.h"
 #include "llvm/ADT/StringMap.h"
 #include "llvm/ADT/SmallString.h"
-#include "llvm/ADT/VectorExtras.h"
 #include <map>
 #include <algorithm>
 #include <functional>