Update to match mainline ConstantStruct::get API change. Also, use

ConvertType on InitListExprs as they are being converted.  This is
needed for a forthcoming patch, and improves the IR generated anyway
(see additional type names in testcases). 

This patch also converts a bunch of std::vector's in CGObjCMac to use
C arrays.  There are a ton more that should be converted as well.

llvm-svn: 133413