51354116: Calling addMotionEffect on image view causes "API called on a background thread: -[UIApplication applicationState]" warning

[openradar-mirror]

Description

Area:
Core Motion

Adding a motion effect to UIImageView causes a UI warning that application state was used on a background thread (by CoreMotion)

Steps to Reproduce:
Call addMotionEffect on UIImageView on main thread.

Expected Results:
No warning

Actual Results:
Main Thread Checker: UI API called on a background thread: -[UIApplication applicationState]
PID: 15886, TID: 4224621, Thread name: com.apple.CoreMotion.MotionThread, Queue name: com.apple.root.default-qos.overcommit, QoS: 0
Backtrace:
4 libobjc.A.dylib 0x00000001b021b6f4 + 56
5 CoreMotion 0x00000001b6965638 CoreMotion + 292408
6 CoreMotion 0x00000001b6965b68 CoreMotion + 293736
7 CoreMotion 0x00000001b6965a78 CoreMotion + 293496
8 CoreMotion 0x00000001b69938a8 CoreMotion + 481448
9 CoreMotion 0x00000001b69938ec CoreMotion + 481516
10 CoreFoundation 0x00000001b0fa778c + 28
11 CoreFoundation 0x00000001b0fa7074 + 276
12 CoreFoundation 0x00000001b0fa2368 + 2276
13 CoreFoundation 0x00000001b0fa1764 CFRunLoopRunSpecific + 452
14 CoreFoundation 0x00000001b0fa2498 CFRunLoopRun + 84
15 CoreMotion 0x00000001b6993280 CoreMotion + 479872
16 libsystem_pthread.dylib 0x00000001b0c21920 + 132
17 libsystem_pthread.dylib 0x00000001b0c2187c _pthread_start + 48
18 libsystem_pthread.dylib 0x00000001b0c29dcc thread_start + 4

Version/Build:
iOS 12.2 – iPhone Xs

Product Version: 12.0
Created: 2019-06-03T13:18:47.487446
Originated: 2019-03-06T00:00:00
Open Radar Link: http://www.openradar.me/51354116