Add accessor for the LLVMContext.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@174824 91177308-0d34-0410-b5e6-96231b3b80d8
attempt to defeat a gcc warning that is breaking a -Werror buildbot.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@174825 91177308-0d34-0410-b5e6-96231b3b80d8