This is a transitory commit for __dynamic_cast. It contains debugging...

This is a transitory commit for __dynamic_cast.  It contains debugging statements that are not intended to be in the finished product.  However some of the dubbing statements themselves contain important documentation such as how to navigate a __class_type_info hierarchy, documenting object offset and inheritance access.  The intention is that this debugging code will migrate into both actual code and comments.  And capturing it here so that there is no chance this stuff will be lost.

llvm-svn: 147898