Patch: fix java.nio.DirectByteBufferImpl memory ownership bug

[Tom Tromey]

>>>>> "Anthony" == Anthony Green <green@redhat.com> writes:

Anthony> If DirectByteBufferImpl is created with a raw buffer pointer,
Anthony> via JNI say, then we need to set "owner" to null.  If we
Anthony> don't do this, then our finalizer will try to free() this
Anthony> memory resulting in badness.  This is explained in the
Anthony> comments at the top of the source file.

Anthony> Ok for HEAD and 4.0 branch?

Yes, thanks.
Please mention "PR libgcj/20727" in the ChangeLog entry.

Tom