Clean up backup code.

Signal/src/ViewControllers/HomeViewController.m

@@ -284,10 +284,6 @@ typedef NS_ENUM(NSInteger, CellState) { kArchiveState, kInboxState };
     }
 
     [self updateBarButtonItems];
-
-    dispatch_async(dispatch_get_main_queue(), ^{
-        [self settingsButtonPressed:nil];
-    });
 }
 
 - (void)viewDidAppear:(BOOL)animated

Signal/src/util/OWSBackup.m

@@ -111,9 +111,7 @@ NS_ASSUME_NONNULL_BEGIN
 {
     OWSAssert(value);
 
-    // TODO: This should eventually be the backup key stored in the Signal Service
-    //       and retrieved with the backup PIN.  It will eventually be stored in
-    //       the keychain.
+    // TODO: Use actual key.
     [self.dbConnection setObject:value
                           forKey:OWSBackup_BackupKeyKey
                     inCollection:OWSPrimaryStorage_OWSBackupCollection];
@@ -124,8 +122,7 @@ NS_ASSUME_NONNULL_BEGIN
     NSData *_Nullable result =
         [self.dbConnection objectForKey:OWSBackup_BackupKeyKey inCollection:OWSPrimaryStorage_OWSBackupCollection];
     if (!result) {
-        // TODO: This is temporary measure until we have proper private key
-        //       storage in the service.
+        // TODO: Use actual key.
         const NSUInteger kBackupPrivateKeyLength = 32;
         result = [Randomness generateRandomBytes:kBackupPrivateKeyLength];
         [self setBackupPrivateKey:result];
@@ -208,18 +205,16 @@ NS_ASSUME_NONNULL_BEGIN
     NSDate *_Nullable lastExportSuccessDate = self.lastExportSuccessDate;
     NSDate *_Nullable lastExportFailureDate = self.lastExportFailureDate;
     // Wait N hours before retrying after a success.
-    //
-    // TODO: Use actual values in production.
-    //    const NSTimeInterval kRetryAfterSuccess = 24 * kHourInterval;
-    const NSTimeInterval kRetryAfterSuccess = 0;
+    const NSTimeInterval kRetryAfterSuccess = 24 * kHourInterval;
+    // TODO: Remove.
+    //    const NSTimeInterval kRetryAfterSuccess = 0;
     if (lastExportSuccessDate && fabs(lastExportSuccessDate.timeIntervalSinceNow) < kRetryAfterSuccess) {
         return NO;
     }
     // Wait N hours before retrying after a failure.
-    //
-    // TODO: Use actual values in production.
-    //    const NSTimeInterval kRetryAfterFailure = 6 * kHourInterval;
-    const NSTimeInterval kRetryAfterFailure = 0;
+    const NSTimeInterval kRetryAfterFailure = 6 * kHourInterval;
+    // TODO: Remove.
+    //    const NSTimeInterval kRetryAfterFailure = 0;
     if (lastExportFailureDate && fabs(lastExportFailureDate.timeIntervalSinceNow) < kRetryAfterFailure) {
         return NO;
     }

Signal/src/util/OWSBackupJob.h

@@ -15,8 +15,7 @@ typedef void (^OWSBackupJobCompletion)(NSError *_Nullable error);
 
 @protocol OWSBackupJobDelegate <NSObject>
 
-// TODO: This should eventually be the backup key stored in the Signal Service
-//       and retrieved with the backup PIN.
+// TODO: Use actual key.
 - (nullable NSData *)backupKey;
 
 // Either backupJobDidSucceed:... or backupJobDidFail:... will