Clicking the file patch view doesn't select a line/hunk unless the view is already focused

[maxbrunsfeld]

Steps to Reproduce

1. Click a file in the commit panel (focuses the commit panel)
2. Click a line in the newly-opened file patch view

Expected behavior:

The file patch view is focused and the clicked line is selected.

Actual behavior:

The file patch view is focused, but nothing is selected.

[smashwilson]

This one was fixed as part of #777. 🌠