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

Originator:karaiskc
Number:rdar://51354116 Date Originated:3/6/2019
Status:Open Resolved:
Product:iOS Product Version:12.0
Classification:Bug Reproducible:YES
 
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 <redacted> + 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 <redacted> + 28
11  CoreFoundation                      0x00000001b0fa7074 <redacted> + 276
12  CoreFoundation                      0x00000001b0fa2368 <redacted> + 2276
13  CoreFoundation                      0x00000001b0fa1764 CFRunLoopRunSpecific + 452
14  CoreFoundation                      0x00000001b0fa2498 CFRunLoopRun + 84
15  CoreMotion                          0x00000001b6993280 CoreMotion + 479872
16  libsystem_pthread.dylib             0x00000001b0c21920 <redacted> + 132
17  libsystem_pthread.dylib             0x00000001b0c2187c _pthread_start + 48
18  libsystem_pthread.dylib             0x00000001b0c29dcc thread_start + 4

Version/Build:
iOS 12.2 – iPhone Xs

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