Patch Set 2: I would prefer that you didn't submit this

I tried with two repositories and found the following scenario to fail:
- show history for first repository
- in repositories view select second repository and click "Open in History"
- the History View gets the focus but the history is not switched to the one for the second repository, instead still the history of the first repository is displayed.

- can we rename the context menu entry to "Show in History" instead of "Open in History" to make this consistent with the entry in the team menu ?

- could you split the change into several ones ? Looks like changing to use Preference actions and adjusting handlers to deal with File are independent from the rest.