Make sure platform views are isolated from the engine's GL context #41620
Description
On iOS we may be passing control to a platform view while the GPU and platform threads are merged and the engine's GL context is current.
If the platform view does not change threads before using GL (which seems to be the case on recent versions of Google Maps) the platform view and the engine may be polluting each others GL state.
I believe this is the root cause for #34509