Improve AST dumping:

1) When dumping a declaration that declares a name for a type, also dump the named type.
 2) Add a #pragma clang __debug dump X, that dumps the lookup results for X in
    the current context.

llvm-svn: 257529

clang/lib/Parse/Parser.cpp

@@ -668,6 +668,9 @@ Parser::ParseExternalDeclaration(ParsedAttributesWithRange &attrs,
   case tok::annot_pragma_ms_pragma:
     HandlePragmaMSPragma();
     return DeclGroupPtrTy();
+  case tok::annot_pragma_dump:
+    HandlePragmaDump();
+    return DeclGroupPtrTy();
   case tok::semi:
     // Either a C++11 empty-declaration or attribute-declaration.
     SingleDecl = Actions.ActOnEmptyDeclaration(getCurScope(),