Merge "libbinder: keep ashmem size >= 0"

                if ((outAshmemSize != nullptr) && ashmem_valid(obj.handle)) {

                    int size = ashmem_get_size_region(obj.handle);

                    if (size > 0) {

                        *outAshmemSize -= size;

                        // ashmem size might have changed since last time it was accounted for, e.g.

                        // in acquire_object(). Value of *outAshmemSize is not critical since we are

                        // releasing the object anyway. Check for integer overflow condition.

                        *outAshmemSize -= std::min(*outAshmemSize, static_cast<size_t>(size));

                    }

                }