Revert "Now allowing the custom nav bar to take up the whole space on iOS" (#2404)
* Revert "Improve getCurrentlyVisibleScreenId on iOS with drawers. (#2052)"
This reverts commit 2c30a52bb9.
* Revert "introducing navbar shadow on iOS (#2339)"
This reverts commit 8fd496e0c9.
* Revert "This fixes an issue with a custom title-view (which has a title and a subtitle) appearing at the left side of the nav-bar instead of the center during a transition animation: when a screen with this title-view is being pushed or when you pop back to it. (#2384)"
This reverts commit 3f7f6c2612.
* Revert "Now allowing the custom nav bar to take up the whole space on iOS (#2306)"
This reverts commit 74a02ccfc5.