Clean up ahead of PR.

SignalServiceKit/src/Messages/OWSDeliveryReceiptManager.m

@@ -10,6 +10,7 @@
 #import "SSKEnvironment.h"
 #import "TSContactThread.h"
 #import "TSYapDatabaseObject.h"
+#import <Reachability/Reachability.h>
 #import <SignalServiceKit/SignalServiceKit-Swift.h>
 
 NS_ASSUME_NONNULL_BEGIN
@@ -20,6 +21,8 @@ NSString *const kDeliveryReceiptManagerCollection = @"kDeliveryReceiptManagerCol
 
 @property (nonatomic, readonly) YapDatabaseConnection *dbConnection;
 
+@property (nonatomic) Reachability *reachability;
+
 // Should only be accessed on the serialQueue.
 @property (nonatomic) BOOL isProcessing;
 
@@ -42,10 +45,17 @@ NSString *const kDeliveryReceiptManagerCollection = @"kDeliveryReceiptManagerCol
         return self;
     }
 
+    self.reachability = [Reachability reachabilityForInternetConnection];
+
     _dbConnection = primaryStorage.newDatabaseConnection;
 
     OWSSingletonAssert();
 
+    [[NSNotificationCenter defaultCenter] addObserver:self
+                                             selector:@selector(reachabilityChanged)
+                                                 name:kReachabilityChangedNotification
+                                               object:nil];
+
     // Start processing.
     [AppReadiness runNowOrWhenAppIsReady:^{
         [self scheduleProcessing];
@@ -96,6 +106,12 @@ NSString *const kDeliveryReceiptManagerCollection = @"kDeliveryReceiptManagerCol
 - (void)process {
     OWSLogVerbose(@"Processing outbound delivery receipts.");
 
+    if (!self.reachability.isReachable) {
+        // No network availability; abort.
+        self.isProcessing = NO;
+        return;
+    }
+
     NSMutableDictionary<NSString *, NSSet<NSNumber *> *> *deliveryReceiptMap = [NSMutableDictionary new];
     [self.dbConnection readWithBlock:^(YapDatabaseReadTransaction *transaction) {
         [transaction enumerateKeysAndObjectsInCollection:kDeliveryReceiptManagerCollection
@@ -221,6 +237,12 @@ NSString *const kDeliveryReceiptManagerCollection = @"kDeliveryReceiptManagerCol
     });
 }
 
+- (void)reachabilityChanged {
+    OWSAssertIsOnMainThread();
+
+    [self scheduleProcessing];
+}
+
 @end
 
 NS_ASSUME_NONNULL_END

SignalServiceKit/src/Messages/OWSMessageManager.m

@@ -507,12 +507,6 @@ NS_ASSUME_NONNULL_BEGIN
     }
 }
 
-- (void)sendDeliveryReceiptForEnvelope:(SSKProtoEnvelope *)envelope {
-    dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0),
-        ^ {
-        });
-}
-
 - (void)sendGroupInfoRequest:(NSData *)groupId
                     envelope:(SSKProtoEnvelope *)envelope
                  transaction:(YapDatabaseReadWriteTransaction *)transaction