Code browser tooltips navigation broken

[David Nolden]

I've debugged and fixed it now. There were some other problems in the
"doNavigate" function (see commit).

The basic underlying issue was that "m_currentNavigationWidget.data()"
as well as one of the "contextView->navigationWidget()" were exactly
the same object(see showToolTip), and thus the command was sent twice
to the same navigation widget. It's strange that you couldn't
reproduce this, maybe you had no context-browser toolview when you did
the testing?

Greetings, David