When creating typedefs, don't call Type::GetName() since that might...

When creating typedefs, don't call Type::GetName() since that might recursively call "lldb_private::Type::ResolveClangType(lldb_private::Type::ResolveStateTag)" and cause a crash. A lldb_private::Type should have a valid name if it is created without a backing CompilerType. Also provide a name that we can recognize so if we see it in a as the typename of a variable, we will know to check it out. This crash is happening quite a bit and we need to determine if this is due to incorrect debug info, or just due to some bug in LLDBD.

<rdar://problem/25192037>

llvm-svn: 264762