Allow for folly::exception_wrapper in ClientReceiveState
Summary:
This diff allows us to use folly::exception_wrapper in ClientReceiveState. Existing use cases are still supported (crs.exception() still returns an exception_ptr no matter what), but we can now choose to set an exception without throwing first.
On the folly side, add some new functions for making an exception_ptr from an exception_wrapper.
Test Plan: Reran unit tests
Reviewed By: davejwatson@fb.com
FB internal diff:
D1307027
@override-unit-failures