LowerTypeTests: Add import/export support for targets without absolute symbol constants.

The rationale is the same as for r312967.

Differential Revision: https://reviews.llvm.org/D37408

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@312968 91177308-0d34-0410-b5e6-96231b3b80d8
16 files changed