Fix bugs in Fixture Search

[lilyCalla]

Bugs fixed:

• selecting or deselecting a fixture with Fixture Groups panel open results in a segfault
• Escape erases the names of fixtures and universes
• Switching from Fixture Groups view to another view in the left panel and then switching back to fixture view does not clear filter until the search button is clicked again, without any visual indication that a filter is still active

[coveralls]

coverage: 32.068%. remained the same
when pulling 6bf200f on lilyCalla:fixture-select-segfault
into 3150b44 on mcallegari:master.

[lilyCalla]

All stylistic issues resolved

[mcallegari]

I cannot reproduce the crash mentioned in the OP.
Can you please explain exactly how to reproduce it?

[lilyCalla]

Ok sorry, forgot an important part of the crash.

Search for with a string that the filter you're about to click on does not match (such that it won't appear in the fixture group view). Then select it in the 2d view, and the application crashes

[mcallegari]

Thanks 👍