* Better GTK+ Menu color support
* Fix 'invisible menu' issue (#12275)
* Now updates menu text color when focus changes!
* Better caching of colors when system theme changes
* Removed all GTK+ deprecation warnings from menubar
* Don't highlight menu text on mouseover in GTK+
* Fix textColor declaration scope error
* Simplify FocusManager connection management a bit
* Make the linter happy
* Decouple MenuBar view recoloring from rebuilding
This way we don't need to rebuild the subview each time a recolor
is needed, e.g. when window focus changes or the system theme changes
* Don't iterate child views if we don't need to
* Move variable declaration outside of a loop
* More efficient iteration of MenuBar children
* Cleaner MenuButton bounds testing
* Fix oops
* Add a nullptr check in MenuBar::GetItemCount()
* Simplify iteration in MenuBar::RebuildChildren()
* Make the linter happy
* Fix signed-unsigned comparison
* Remove declarations of nonexistent methods
* Make SubmenuButton accessor const
* Cleaner accelerator iteration
* Windows fixes
