Add some basic RefControl tests for delegated ownership

While trying to understand what was wrong in issue 672 I started
to write up some unit tests for RefControl.  These don't give us
a whole lot of code coverage here, but its a simple start that
we can build on later.

Change-Id: Ib216a3d911c8447004528074a000e9424bcd711d
Signed-off-by: Shawn O. Pearce <sop@google.com>
2 files changed