style cleanup, no functional changes

// FREEBIE

Signal/src/environment/Migrations/OWS101ExistingUsersBlockOnIdentityChange.m

@@ -10,6 +10,11 @@ NS_ASSUME_NONNULL_BEGIN
 // Increment a similar constant for every future DBMigration
 static NSString *const OWS101ExistingUsersBlockOnIdentityChangeMigrationId = @"101";
 
+/**
+ * This migration is no longer necessary, but deleting a class is complicated in Yap
+ * and involves writing another migration to remove the previous. It seemed like the
+ * simplest/safest thing to do would be to just leave it.
+ */
 @implementation OWS101ExistingUsersBlockOnIdentityChange
 
 + (NSString *)migrationId
@@ -20,10 +25,7 @@ static NSString *const OWS101ExistingUsersBlockOnIdentityChangeMigrationId = @"1
 - (void)runUpWithTransaction:(YapDatabaseReadWriteTransaction *)transaction
 {
     DDLogWarn(@"[OWS101ExistingUsersBlockOnIdentityChange] has been obviated.");
-    //    DDLogWarn(@"[OWS101ExistingUsersBlockOnIdentityChange] Opting existing user into 'blocking' on identity
-    //    changes."); TSPrivacyPreferences *preferences = [TSPrivacyPreferences sharedInstance];
-    //    preferences.shouldBlockOnIdentityChange = YES;
-    //    [preferences saveWithTransaction:transaction];
+    OWSAssert(NO);
 }
 
 @end

Signal/src/environment/Migrations/OWS104CreateRecipientIdentities.m

@@ -14,7 +14,7 @@ NS_ASSUME_NONNULL_BEGIN
 static NSString *const OWS104CreateRecipientIdentitiesMigrationId = @"104";
 
 /**
- * New SN behavaior requires tracking additional state - not just the identity key data.
+ * New SN behavior requires tracking additional state - not just the identity key data.
  * So we wrap the key, along with the new meta-data in an OWSRecipientIdentity.
  */
 @implementation OWS104CreateRecipientIdentities

Signal/src/environment/Migrations/OWSDatabaseMigrationRunner.m

@@ -4,7 +4,6 @@
 
 #import "OWSDatabaseMigrationRunner.h"
 #import "OWS100RemoveTSRecipientsMigration.h"
-//#import "OWS101ExistingUsersBlockOnIdentityChange.h"
 #import "OWS102MoveLoggingPreferenceToUserDefaults.h"
 #import "OWS103EnableVideoCalling.h"
 #import "OWS104CreateRecipientIdentities.h"
@@ -29,8 +28,6 @@ NS_ASSUME_NONNULL_BEGIN
 {
     return @[
         [[OWS100RemoveTSRecipientsMigration alloc] initWithStorageManager:self.storageManager],
-        // Old nonblocking migration is no longer necessary.
-        // [[OWS101ExistingUsersBlockOnIdentityChange alloc] initWithStorageManager:self.storageManager],
         [[OWS102MoveLoggingPreferenceToUserDefaults alloc] initWithStorageManager:self.storageManager],
         [[OWS103EnableVideoCalling alloc] initWithStorageManager:self.storageManager],
         [[OWS104CreateRecipientIdentities alloc] initWithStorageManager:self.storageManager]