Some code in the review dialog was saving the model when the state of the "Ship

It!" checkbox was changed, which was causing some glitchy behavior with the

display of the header (when there were comments present). We already have code

to save the state of this checkbox when the dialog is being closed, so there's

no reason to do so every time it's clicked.

Added a diff comment, then opened the review dialog and clicked "Ship It".

Before this change, the header editor would close, potentially without saving

the data therein. After, it stays open.