Also improve the code a bit by using a boolean to know whether to focus
the editor rather than always pass the key value and check it against
enter-or-return in the callee side.

Patch by Dimitar Zhekov, thanks!

git-svn-id: https://geany.svn.sourceforge.net/svnroot/geany/trunk@5887 ea778897-0a13-0410-b9d1-a72fbfd435f5