Remove unused diagnostic + dead test for it.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@205220 91177308-0d34-0410-b5e6-96231b3b80d8
MS ABI: Document the '\xc1' to '\xda' manglings

No functionality change.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@205223 91177308-0d34-0410-b5e6-96231b3b80d8
MS ABI: mangleStringLiteral shouldn't rely on the host's endianness

No test case is needed, the one in-tree is sufficient.  The build-bot
never emailed me because something else had upset it.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@205225 91177308-0d34-0410-b5e6-96231b3b80d8
Introduced an attribute syntax-neutral method for parsing attribute arguments that is currently being used by GNU and C++-style attributes. This allows C++11 attributes with argument lists to be handled properly, fixing the "deprecated", "type_visibility", and capability-related attributes with arguments.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@205226 91177308-0d34-0410-b5e6-96231b3b80d8