<rdar://problem/10522194>

Fixed an issue where if we have the DWARF equivalent of:

struct foo;

class foo { ... };

Or vice versa, we wouldn't be able to find the complete type. Since many
compilers allow forward declarations to have struct and definitions to have
class, we need to be able to deal with both cases. This commit fixes this in
the DWARF parser.

llvm-svn: 145733