Move UTF conversion routines from clang/lib/Basic to llvm/lib/Support

This is required to use them in TableGen.

llvm-svn: 173924
diff --git a/clang/lib/Frontend/TextDiagnostic.cpp b/clang/lib/Frontend/TextDiagnostic.cpp
index aba90f6..f7c0d60 100644
--- a/clang/lib/Frontend/TextDiagnostic.cpp
+++ b/clang/lib/Frontend/TextDiagnostic.cpp
@@ -8,13 +8,13 @@
 //===----------------------------------------------------------------------===//
 
 #include "clang/Frontend/TextDiagnostic.h"
-#include "clang/Basic/ConvertUTF.h"
 #include "clang/Basic/DiagnosticOptions.h"
 #include "clang/Basic/FileManager.h"
 #include "clang/Basic/SourceManager.h"
 #include "clang/Lex/Lexer.h"
 #include "llvm/ADT/SmallString.h"
 #include "llvm/ADT/StringExtras.h"
+#include "llvm/Support/ConvertUTF.h"
 #include "llvm/Support/ErrorHandling.h"
 #include "llvm/Support/Locale.h"
 #include "llvm/Support/MemoryBuffer.h"