0.15.1869: branch graph sometimes blanking on context change/refresh

[claybridges]

On certain changes to repository or context, GitX seems to refresh to a blank branch graph. So far this has happened to me when:

• switching from Commit to History views
• making changes from terminal

Workaround: forcing another refresh, cmd-R, shows the graph.

[rjmunro]

Since upgrading, I'm seeing this occasionally as well.

[nuthatch]

Glad I found this. Thought it might be some new "feature" ...i'm only seeing commits since the branch was created, nothing before that, until I hit cmd-R. That works.

[loosebits]

I see this on rebasing from the shell

[emilykfox]

I also see this issue when doing a pull from shell. It occurs far more regularly when I'm looking at a commit that is not the latest commit. It occurs in both Detailed View and Tree View.