Apparently we need to update the node's size after a write on a filehandle.
Finder stats it (the node, not the handle) while writing and complains if it's
not the right size.
Change-Id: Ie3e98328a182a4bbb3230c5190e1d57d0d3fb075
Currently one a few stats are tracked, but more can be added easily now.
The only test using this is using it to verify that the read-only open optimization
is used.
Change-Id: I1e2fb8a0222ade82631670d7c51e684778d031ae
Brad Fitzpatrick