Solves IDEA-107376

The problem was due ```myTabbedPane``` is always null when there are not tabs (Editor / Editor Tabs / Tab Appearance set to none) therefor never requesting focus. 

I added a else case to make use of ```IdeFocusManager``` so it will use the ```findInstanceByComponent``` with the current panel and then request the focus to the editor.

Issue reference http://youtrack.jetbrains.com/issue/IDEA-107376