If a test case panics while holding a static method's internal Mutex locked, for example by violating a times() constraint, then clear the Mutex's poison during Drop. We're going to delete all of its Expectations anyway, so there's no data to be poisoned.
If a test case panics while holding a static method's internal Mutex locked, for example by violating a times() constraint, then clear the Mutex's poison during Drop. We're going to delete all of its Expectations anyway, so there's no data to be poisoned.
Requires nightly.
Fixes #515