Fix location bar being wrongly aligned on first startup
When starting Dolphin the very first time, the spacing in front of the location bar is wrong. This doesn't produce any usability issues but might produce a bad first impression. The wrong spacing fixes itself if Dolphin is resized or restarted. The spacing also reduces itself if the space is needed by a longer url.
I do not know a way to reproduce the wrong spacing aside from reinstalling the whole system.
@fvogt confirmed that the first commit of this MR fixes the bug. It does so by completely updating all cached geometry every time adjustSpacing() is called. Because that happens once on a timer 100 ms after every url change, it will happen once shortly after the window is shown. At that point all geometry is where it should be.
The second commit cleans those changes up and refactors the updating of cached geometry into a ViewGeometriesHelper class which is a private nested class in DolphinNavigatorsWidgetAction. Previously the logic of this new helper class was divided between DolphinTabPage and DolphinNavigatorsWidgetAction which get slimmed down in the process.
test plan: I hope @fvogt can test this once more after code review is done.
If you can't reproduce the bug then the only thing to look out for are changes introduced by this MR because there shouldn't be any.