IRTests/WaymarkTest.cpp: Fix in --vg-leak.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173239 91177308-0d34-0410-b5e6-96231b3b80d8
llvm/unittests: Use OwningPtr to fix --vg-leak.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173240 91177308-0d34-0410-b5e6-96231b3b80d8