Produce type parameter declarations for Objective-C type parameters,
and attach lists of type parameters to Objective-C classes,
categories, forward declarations, and extensions as
appropriate. Perform semantic analysis of type bounds for type
parameters, both in isolation and across classes/categories/extensions
to ensure consistency.
Also handle (de-)serialization of Objective-C type parameter lists,
along with sundry other things one must do to add a new declaration to
Clang.
Note that Objective-C type parameters are typedef name declarations,
like typedefs and C++11 type aliases, in support of type erasure.
Part of rdar://problem/6294649.
llvm-svn: 241541