[Bugpoint] Use `unique_ptr` correctly.
[Bugpoint] Use `unique_ptr` correctly.

Moving Modules into `testMergedProgram` is incorrect (and causes segmentation
faults) since all callers expect to retain ownership. This is evidenced by the
later calls to `unique_ptr<Module>::get` in the same function.

Differential Revision: https://reviews.llvm.org/D31727

git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@299596 91177308-0d34-0410-b5e6-96231b3b80d8

GPUOpen-Drivers/llvm,llvm-mirror/llvm,GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm,apple/swift-llvm,llvm-mirror/llvm,GPUOpen-Drivers/llvm,llvm-mirror/llvm,llvm-mirror/llvm,llvm-mirror/llvm,llvm-mirror/llvm,apple/swift-llvm,apple/swift-llvm,GPUOpen-Drivers/llvm,llvm-mirror/llvm,GPUOpen-Drivers/llvm,llvm-mirror/llvm,apple/swift-llvm,llvm-mirror/llvm,apple/swift-llvm,GPUOpen-Drivers/llvm,apple/swift-llvm,apple/swift-llvm,apple/swift-llvm