WholeProgramDevirt: Add any unsuccessful llvm.type.checked.load...

WholeProgramDevirt: Add any unsuccessful llvm.type.checked.load devirtualizations to the list of llvm.type.test users.

Any unsuccessful llvm.type.checked.load devirtualizations will be translated
into uses of llvm.type.test, so we need to add the resulting llvm.type.test
intrinsics to the function summaries so that the LowerTypeTests pass will
export them.

Differential Revision: https://reviews.llvm.org/D29808

llvm-svn: 296939