comment parsing. Keep the original command format 
in AST for source fidelity and use it in diagnostics 
to refer to the original format. // rdar://13066276


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@176387 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/AST/CommentLexer.cpp b/lib/AST/CommentLexer.cpp
index cee086e..da865d2 100644
--- a/lib/AST/CommentLexer.cpp
+++ b/lib/AST/CommentLexer.cpp
@@ -298,6 +298,7 @@
     switch(*TokenPtr) {
       case '\\':
       case '@': {
+        T.HDCommand = (*TokenPtr == '@');
         TokenPtr++;
         if (TokenPtr == CommentEnd) {
           formTextToken(T, TokenPtr);