Add missing include.

llvm-svn: 113859

llvm/include/llvm/TypeSymbolTable.h

@@ -16,12 +16,11 @@
 
 #include "llvm/Type.h"
 #include "llvm/ADT/StringRef.h"
+#include "llvm/System/DataTypes.h"
 #include <map>
 
 namespace llvm {
 
-class StringRef;
-
 /// This class provides a symbol table of name/type pairs with operations to
 /// support constructing, searching and iterating over the symbol table. The
 /// class derives from AbstractTypeUser so that the contents of the symbol