V1 had two SideMenu implementations. In v2 we've decided to stick with one and for some reason
code related to the unsupported implementation was left in the project.

This approach is still not ideal as it assumes there's a visible stack somewhere in the Hierarchy.
It's better than the current implementation so I'm pushing it and will reiterate in the future if needed.

* Fixed constants bug (closes #4807)

* Fixed constants bug (closes #4807)

* Constants support

* Change Navigation.constants() to an async function on Android

Also added topBarHeight and bottomTabsHeight