symbol-z-order not respected when symbols are rendered at different coordinates

[samfader]

Steps to reproduce

1. Pull down symbolzorder-example (symbolZOrder example ios-sdk-examples#245) branch in the ios-sdk-examples app.
2. Run the app and open the ObjC/Swift version of the Specify z order of features in a symbol layer example.
3. Try switching between the two options presented in the toggle at the bottom of the screen.

Expected behavior

The icons are arranged in the proper order depending on the symbol-z-order.

Here is a GL JS example (uploaded as a zip because it includes images) that contains two files - one where the symbol-z-order is set to source, and another viewport-y. You'll see the z-order of the shapes changes as expected.

Actual behavior

The icons stay in the same arrangement (z-order).

GL JS
source

viewport_y

iOS

Configuration

Mapbox SDK versions: 4.5.0
iOS/macOS versions: iOS 12.1
Device/simulator models: iPhone XS Max
Xcode version: 10.1

cc @captainbarbosa @ryanhamley

[samfader]

Not specifically sure what fixed this but it doesn't appear to be an issue anymore.

[pozdnyakov]

Not specifically sure what fixed this but it doesn't appear to be an issue anymore.

Must be fixed by #14486

[samfader]

@pozdnyakov That was my thinking as well and why I came back to this, but I also noticed it was working on v4.5.0 of the iOS SDK. Not sure if I was doing something wrong before or what specifically is going on, but it does appear to be working either way.