Move initialization of PHPhotoLibrary and PHCachingImageManager to background

[leonspok]

We have freezes (not deadlocks) inside PHCachingImageManager initialization. According to stach trace, it might be related to PHPhotoLibrary singleton initialization. So it was moved to background thread to avoid blocking UI.

Thread 0:
0   libsystem_kernel.dylib               0x00000001e61db428 __semwait_signal + 8
1   libsystem_c.dylib                    0x00000001e61503cc sleep + 44
2   CoreData                             0x00000001e9181634 -[NSXPCStore sendMessage:fromContext:interrupts:error:] + 868
3   CoreData                             0x00000001e91e6c98 -[NSXPCStore loadMetadata:] + 344
4   CoreData                             0x00000001e92ca290 __91-[NSPersistentStoreCoordinator addPersistentStoreWithType:configuration:URL:options:error:]_block_invoke + 1544
5   CoreData                             0x00000001e92d6be4 gutsOfBlockToNSPersistentStoreCoordinatorPerform + 212
6   libdispatch.dylib                    0x00000001e607e484 _dispatch_client_callout + 16
7   libdispatch.dylib                    0x00000001e605e744 _dispatch_lane_barrier_sync_invoke_and_complete + 56
8   CoreData                             0x00000001e92c79d4 _perform + 200
9   CoreData                             0x00000001e9161ec8 -[NSPersistentStoreCoordinator addPersistentStoreWithType:configuration:URL:options:error:] + 384
10  PhotoLibraryServices                 0x00000001f44405e0 +[PLManagedObjectContext _configureXPCPersistentStoreCoordinator:] + 616
11  AssetsLibraryServices                0x00000001f402778c __pl_dispatch_sync_block_invoke + 36
12  libdispatch.dylib                    0x00000001e607e484 _dispatch_client_callout + 16
13  libdispatch.dylib                    0x00000001e605e744 _dispatch_lane_barrier_sync_invoke_and_complete + 56
14  AssetsLibraryServices                0x00000001f402775c pl_dispatch_sync + 68
15  PhotoLibraryServices                 0x00000001f44408bc +[PLManagedObjectContext sharedPersistentStoreCoordinator] + 152
16  PhotoLibraryServices                 0x00000001f443b560 -[PLManagedObjectContext initWithConcurrencyType:useSharedPersistentStoreCoordinator:] + 124
17  PhotoLibraryServices                 0x00000001f443b3d8 +[PLManagedObjectContext contextForPhotoLibrary:name:] + 200
18  PhotoLibraryServices                 0x00000001f435e528 -[PLPhotoLibrary _loadDatabase:] + 416
19  PhotoLibraryServices                 0x00000001f4352168 -[PLPhotoLibrary initWithTransientContext:name:pathManager:] + 580
20  Photos                               0x00000001f53b0fa4 -[PHPhotoLibrary photoLibrary] + 108
21  Photos                               0x00000001f53b1f80 -[PHPhotoLibrary registerChangeObserver:] + 168
22  Photos                               0x00000001f5391630 -[PHImageManager init] + 420
23  Photos                               0x00000001f53957bc -[PHCachingImageManager init] + 40
24  ChattoAdditions                      0x000000010360ed84 PhotosInputDataProvider.init() + 159108 (PhotosInputDataProvider.swift:63)

[codecov-io]

Codecov Report

Merging #566 into photo-library-fix-freeze will decrease coverage by 0.36%.
The diff coverage is 0%.

@@                     Coverage Diff                      @@
##           photo-library-fix-freeze     #566      +/-   ##
============================================================
- Coverage                     59.97%   59.61%   -0.37%     
============================================================
  Files                            87       87              
  Lines                          3945     3969      +24     
============================================================
  Hits                           2366     2366              
- Misses                         1579     1603      +24

Impacted Files	Coverage Δ
...e/Input/Photos/Photo/PhotosInputDataProvider.swift	0% <0%> (ø)	⬆️
...dditions/Source/Input/Photos/PhotosInputView.swift	1.69% <0%> (-0.05%)	⬇️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 5995970...8813401. Read the comment docs.