Use StringRef's case transformation methods.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@143889 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/utils/TableGen/ClangDiagnosticsEmitter.cpp b/utils/TableGen/ClangDiagnosticsEmitter.cpp
index da2fb70..7a5eb1d 100644
--- a/utils/TableGen/ClangDiagnosticsEmitter.cpp
+++ b/utils/TableGen/ClangDiagnosticsEmitter.cpp
@@ -16,7 +16,6 @@
 #include "llvm/Support/Debug.h"
 #include "llvm/Support/Compiler.h"
 #include "llvm/ADT/DenseSet.h"
-#include "llvm/ADT/StringExtras.h"
 #include "llvm/ADT/StringMap.h"
 #include "llvm/ADT/SmallString.h"
 #include "llvm/ADT/VectorExtras.h"
@@ -130,7 +129,7 @@
 void ClangDiagsDefsEmitter::run(raw_ostream &OS) {
   // Write the #if guard
   if (!Component.empty()) {
-    std::string ComponentName = UppercaseString(Component);
+    std::string ComponentName = StringRef(Component).upper();
     OS << "#ifdef " << ComponentName << "START\n";
     OS << "__" << ComponentName << "START = DIAG_START_" << ComponentName
        << ",\n";