title: Crashlytics thread crashed only on iOS13 built with Xcode11
body: <p>My app is crashed only on iOS13 with the following call stack:</p>
  
  <pre><code>#57. Crashed: com.twitter.crashlytics.ios.exception
  0  myapp                          0x105d6d494 CLSProcessRecordAllThreads + 376 (CLSProcess.c:376)
  1  myapp                          0x105d6d87c CLSProcessRecordAllThreads + 407 (CLSProcess.c:407)
  2  myapp                          0x105d5d58c CLSHandler + 26 (CLSHandler.m:26)
  3  myapp                          0x105d6bab4 __CLSExceptionRecord_block_invoke + 198 (CLSException.mm:198)
  4  libdispatch.dylib              0x1be5c100c _dispatch_client_callout + 20
  5  libdispatch.dylib              0x1be5cd804 _dispatch_lane_barrier_sync_invoke_and_complete + 60
  6  myapp                          0x105d6b55c CLSExceptionRecord + 205 (CLSException.mm:205)
  7  myapp                          0x105d6b390 CLSExceptionRecordNSException + 102 (CLSException.mm:102)
  8  myapp                          0x105d6afb4 CLSTerminateHandler() + 258 (CLSException.mm:258)
  9  libc++abi.dylib                0x1be6d9634 std::__terminate(void (*)()) + 20
  10 libc++abi.dylib                0x1be6d8f58 __cxa_get_exception_ptr + 34
  11 libc++abi.dylib                0x1be6d8f10 __cxxabiv1::exception_cleanup_func(_Unwind_Reason_Code, _Unwind_Exception*) + 126
  12 libobjc.A.dylib                0x1be6341f8 _objc_exception_destructor(void*) + 362
  13 Foundation                     0x1bee05434 -[NSISEngine tryToOptimizeReturningMutuallyExclusiveConstraints] + 322
  14 Foundation                     0x1bebfeb94 -[NSISEngine _optimizeWithoutRebuilding] + 72
  15 Foundation                     0x1bebfeaa8 -[NSISEngine optimize] + 116
  16 Foundation                     0x1bebfe718 -[NSISEngine performPendingChangeNotifications] + 116
  17 UIKitCore                      0x1c2e447c4 -[UIView(Hierarchy) layoutSubviews] + 316
  18 UIKitCore                      0x1c23c6948 -[UIButton layoutSubviews] + 596
  19 UIKitCore                      0x1c2e57abc -[UIView(CALayerDelegate) layoutSublayersOfLayer:] + 2156
  20 libobjc.A.dylib                0x1be62faf0 -[NSObject performSelector:withObject:] + 68
  21 QuartzCore                     0x1c53f60f4 -[CALayer layoutSublayers] + 292
  22 QuartzCore                     0x1c53f63fc CA::Layer::layout_if_needed(CA::Transaction*) + 484
  23 QuartzCore                     0x1c5409964 CA::Layer::layout_and_display_if_needed(CA::Transaction*) + 140
  24 QuartzCore                     0x1c534ec1c CA::Context::commit_transaction(CA::Transaction*, double) + 308
  25 QuartzCore                     0x1c5379bd8 CA::Transaction::commit() + 684
  26 QuartzCore                     0x1c537abc0 CA::Transaction::release_thread(void*) + 232
  27 libsystem_pthread.dylib        0x1be62c3c0 _pthread_tsd_cleanup + 584
  28 libsystem_pthread.dylib        0x1be624dbc _pthread_exit + 84
  29 libsystem_pthread.dylib        0x1be626de8 _pthread_wqthread_legacy_worker_wrap + 98
  30 libsystem_pthread.dylib        0x1be626b30 _pthread_wqthread + 424
  31 libsystem_pthread.dylib        0x1be62cc78 start_wqthread + 8
  
  --
  
  Fatal Exception: NSInternalInconsistencyException
  Modifications to the layout engine must not be performed from a background thread after it has been accessed from the main thread.
  0  CoreFoundation                 0x1be919c30 __exceptionPreprocess
  1  libobjc.A.dylib                0x1be6340c8 objc_exception_throw
  2  Foundation                     0x1bee05434 -[NSISEngine tryToOptimizeReturningMutuallyExclusiveConstraints]
  3  Foundation                     0x1bebfeb94 -[NSISEngine _optimizeWithoutRebuilding]
  4  Foundation                     0x1bebfeaa8 -[NSISEngine optimize]
  5  Foundation                     0x1bebfe718 -[NSISEngine performPendingChangeNotifications]
  6  UIKitCore                      0x1c2e447c4 -[UIView(Hierarchy) layoutSubviews]
  7  UIKitCore                      0x1c23c6948 -[UIButton layoutSubviews]
  8  UIKitCore                      0x1c2e57abc -[UIView(CALayerDelegate) layoutSublayersOfLayer:]
  9  libobjc.A.dylib                0x1be62faf0 -[NSObject performSelector:withObject:]
  10 QuartzCore                     0x1c53f60f4 -[CALayer layoutSublayers]
  11 QuartzCore                     0x1c53f63fc CA::Layer::layout_if_needed(CA::Transaction*)
  12 QuartzCore                     0x1c5409964 CA::Layer::layout_and_display_if_needed(CA::Transaction*)
  13 QuartzCore                     0x1c534ec1c CA::Context::commit_transaction(CA::Transaction*, double)
  14 QuartzCore                     0x1c5379bd8 CA::Transaction::commit()
  15 QuartzCore                     0x1c537abc0 CA::Transaction::release_thread(void*)
  16 libsystem_pthread.dylib        0x1be62c3c0 _pthread_tsd_cleanup
  17 libsystem_pthread.dylib        0x1be624dbc _pthread_exit
  18 libsystem_pthread.dylib        0x1be626de8 _pthread_wqthread_legacy_worker_wrap
  19 libsystem_pthread.dylib        0x1be626b30 _pthread_wqthread
  20 libsystem_pthread.dylib        0x1be62cc78 start_wqthread
  </code></pre>
  
  <p>I absolutely do not have any idea, what can occure this problem and how can i reproduce. It crashes randomly. I use Crashlytics v3.14 in my project. Does anybody face with the same problem?</p>