Focus of the URL text input caused animation stutter while the iOS
keyboard visibility toggled from hide to show to hide. To address this,
the Android-specific keyboard dismiss logic is now applied to iOS as
well.

The `layout` conditional was removed in https://git.io/JEDdk, as it is
no longer utilized. However, its prior presence was universally
disabling the block it guarded. Removing the always falsey conditional
caused the block to always run and break the Android animation.

Specifically, when navigating from a full-screen bottom sheet to a
non-full-screen bottom sheet, the `currentHeight` is always `1`. This
results in setting the height without layout animations prior to this
change.