Fetch messages sooner when launched from background

The only reason a notification wakes/launches the app is to fetch
messages.

However, upon launching, especially if the app had been killed, it can
take a second or two before being notified of the notification that woke
us. Rather than wait, just fetch messages ASAP.

// FREEBIE

Signal/src/AppDelegate.m

@@ -818,6 +818,11 @@ static NSString *const kURLHostVerifyPrefix             = @"verify";
     if ([TSAccountManager isRegistered]) {
         DDLogInfo(@"localNumber: %@", [TSAccountManager localNumber]);
 
+        // Fetch messages as soon as possible after launching. In particular, when
+        // launching from the background, without this, we end up waiting some extra
+        // seconds before receiving an actionable push notification.
+        [[Environment getCurrent].messageFetcherJob runAsync];
+
         // This should happen at any launch, background or foreground.
         __unused AnyPromise *promise = [OWSSyncPushTokensJob runWithPushManager:[PushManager sharedManager]
                                                                  accountManager:[Environment getCurrent].accountManager

Signal/src/environment/Environment.h

@@ -27,6 +27,7 @@
 @class CallService;
 @class OWSMessageSender;
 @class NotificationsManager;
+@class OWSMessageFetcherJob;
 
 @interface Environment : NSObject
 
@@ -46,7 +47,7 @@
 @property (nonatomic, readonly) NotificationsManager *notificationsManager;
 @property (nonatomic, readonly) OWSMessageSender *messageSender;
 @property (nonatomic, readonly) OWSPreferences *preferences;
-
+@property (nonatomic, readonly) OWSMessageFetcherJob *messageFetcherJob;
 
 @property (nonatomic, readonly) HomeViewController *homeViewController;
 @property (nonatomic, readonly, weak) UINavigationController *signUpFlowNavigationController;

Signal/src/environment/Environment.m

@@ -13,6 +13,8 @@
 #import "TSGroupThread.h"
 #import <SignalServiceKit/ContactsUpdater.h>
 #import <SignalServiceKit/Threading.h>
+#import <SignalServiceKit/OWSSignalService.h>
+#import <SignalServiceKit/OWSMessageReceiver.h>
 
 static Environment *environment = nil;
 
@@ -23,6 +25,7 @@ static Environment *environment = nil;
             callService = _callService,
             contactsManager = _contactsManager,
             contactsUpdater = _contactsUpdater,
+            messageFetcherJob = _messageFetcherJob,
             messageSender = _messageSender,
             networkManager = _networkManager,
             notificationsManager = _notificationsManager,
@@ -137,6 +140,20 @@ static Environment *environment = nil;
     return _networkManager;
 }
 
+- (OWSMessageFetcherJob *)messageFetcherJob
+{
+    @synchronized(self)
+    {
+        if (!_messageFetcherJob) {
+            _messageFetcherJob =
+                [[OWSMessageFetcherJob alloc] initWithMessageReceiver:[OWSMessageReceiver sharedInstance]
+                                                       networkManager:self.networkManager
+                                                        signalService:[OWSSignalService sharedInstance]];
+        }
+    }
+    return _messageFetcherJob;
+}
+
 - (OWSMessageSender *)messageSender
 {
     OWSAssert(_messageSender != nil);

Signal/src/network/PushManager.m

@@ -52,17 +52,15 @@ NSString *const Signal_Message_MarkAsRead_Identifier = @"Signal_Message_MarkAsRe
 
 - (instancetype)initDefault
 {
-    return [self initWithNetworkManager:[Environment getCurrent].networkManager
+    return [self initWithMessageFetcherJob:[Environment getCurrent].messageFetcherJob
                             storageManager:[TSStorageManager sharedManager]
                              callUIAdapter:[Environment getCurrent].callService.callUIAdapter
-                        messageReceiver:[OWSMessageReceiver sharedInstance]
                              messageSender:[Environment getCurrent].messageSender];
 }
 
-- (instancetype)initWithNetworkManager:(TSNetworkManager *)networkManager
+- (instancetype)initWithMessageFetcherJob:(OWSMessageFetcherJob *)messageFetcherJob
                            storageManager:(TSStorageManager *)storageManager
                             callUIAdapter:(CallUIAdapter *)callUIAdapter
-                       messageReceiver:(OWSMessageReceiver *)messageReceiver
                             messageSender:(OWSMessageSender *)messageSender
 {
     self = [super init];
@@ -72,12 +70,7 @@ NSString *const Signal_Message_MarkAsRead_Identifier = @"Signal_Message_MarkAsRe
 
     _callUIAdapter = callUIAdapter;
     _messageSender = messageSender;
-
-    OWSSignalService *signalService = [OWSSignalService sharedInstance];
-    _messageFetcherJob = [[OWSMessageFetcherJob alloc] initWithMessageReceiver:messageReceiver
-                                                                networkManager:networkManager
-                                                                 signalService:signalService];
-
+    _messageFetcherJob = messageFetcherJob;
     _callBackgroundTask = UIBackgroundTaskInvalid;
     _currentNotifications = [NSMutableArray array];