Summary:public
Create a model of std::unique_ptr in similar fashion to what was done to std::shared_ptr.
For now, we are modeling it as container of raw pointer (no ownership concept).
This time unique_ptr is not derived from std__unique_ptr (unlike shared_ptr, it was easier to not do that) and so we need to provide implementations for all non-member functions per C++ reference:
http://en.cppreference.com/w/cpp/memory/unique_ptr
Reviewed By: dulmarod
Differential Revision: D3048209
fb-gh-sync-id: a9a6455
shipit-source-id: a9a6455