Comment parsing: handle non-builtin commands correctly.  After semantic
analysis registers a command, it becomes a "known" command for the lexer, since
it has an ID.  Having this freedom of choice to register a command is a good
thing since BriefParser does not need this.

But the parser should still invoke the correct semantic analysis method
(actOnUnknownCommand) in this case.

llvm-svn: 163646
diff --git a/clang/lib/AST/CommentCommandTraits.cpp b/clang/lib/AST/CommentCommandTraits.cpp
index ba0aa9a..e7e40fd 100644
--- a/clang/lib/AST/CommentCommandTraits.cpp
+++ b/clang/lib/AST/CommentCommandTraits.cpp
@@ -40,6 +40,7 @@
   CommandInfo *Info = new (Allocator) CommandInfo();
   Info->Name = Name;
   Info->ID = NextID++;
+  Info->IsUnknownCommand = true;
 
   RegisteredCommands.push_back(Info);