It's easier for people to debug, and side-steps the problem that errno
values differ between architectures.
Bug: http://b/17458391
Change-Id: I1db9b2cbb653839d3936b91e37e5cff02671318a
Nobody ever called acquire() so release() was always
equivalent to delete. Just use delete instead so that
people can use unique_ptr directly (or shared_ptr if
they really want refcounts).
Change-Id: I9e3ad5e0f6a4fcc4e02e5a2ff7ef9514fe234415