Fix issue of not being able to swipe away paused downloads.

This is part of a larger refactor to make downloads a foreground
service on all versions of Android. There was a bug that made it so
that paused downloads were not swipeable (and therefore not
cancellable). This CL fixes that bug.

Bug: 747563
Change-Id: If67d34523e0352aaf3b8f5c78967fd1ec3a697a7
Reviewed-on: https://chromium-review.googlesource.com/661940Reviewed-by: David Trainor <dtrainor@chromium.org>
Commit-Queue: Joy Ming <jming@chromium.org>
Cr-Commit-Position: refs/heads/master@{#501450}

chrome/android/java/src/org/chromium/chrome/browser/download/DownloadForegroundService.java

@@ -47,7 +47,14 @@ public class DownloadForegroundService extends Service {
      * Stop the foreground service that is running.
      */
     public void stopDownloadForegroundService(boolean isCancelled) {
-        stopForeground(isCancelled /* kill notification if cancelled */);
+        // If it's not cancelled, just detach the notification from the service, if possible.
+        if (!isCancelled && Build.VERSION.SDK_INT >= 24) {
+            stopForeground(STOP_FOREGROUND_DETACH);
+            return;
+        }
+
+        // Otherwise, just stop the foreground and correct it elsewhere.
+        stopForeground(true);
     }
 
     @Override

chrome/android/java/src/org/chromium/chrome/browser/download/DownloadForegroundServiceManager.java

@@ -197,28 +197,38 @@ public class DownloadForegroundServiceManager {
             // This does not happen for API >= 24.
             if (mPinnedNotificationId != INVALID_NOTIFICATION_ID
                     && mPinnedNotificationId != notificationId && Build.VERSION.SDK_INT < 24) {
-                NotificationManager notificationManager =
-                        (NotificationManager) ContextUtils.getApplicationContext().getSystemService(
-                                Context.NOTIFICATION_SERVICE);
-                notificationManager.notify(mPinnedNotificationId,
-                        mDownloadUpdateQueue.get(mPinnedNotificationId).mNotification);
+                relaunchPinnedNotification();
             }
 
             mPinnedNotificationId = notificationId;
         }
     }
 
+    private void relaunchPinnedNotification() {
+        NotificationManager notificationManager =
+                (NotificationManager) ContextUtils.getApplicationContext().getSystemService(
+                        Context.NOTIFICATION_SERVICE);
+        notificationManager.notify(mPinnedNotificationId,
+                mDownloadUpdateQueue.get(mPinnedNotificationId).mNotification);
+    }
+
     /** Helper code to stop and unbind service. */
 
     @VisibleForTesting
     void stopAndUnbindService(boolean isCancelled) {
         mIsServiceBound = false;
-        mPinnedNotificationId = INVALID_NOTIFICATION_ID;
 
         if (mBoundService != null) {
             stopAndUnbindServiceInternal(isCancelled);
             mBoundService = null;
         }
+
+        // If the download isn't cancelled,  need to relaunch the notification so it is no longer
+        // pinned to the foreground service.
+        if (!isCancelled && Build.VERSION.SDK_INT < 24) {
+            relaunchPinnedNotification();
+        }
+        mPinnedNotificationId = INVALID_NOTIFICATION_ID;
     }
 
     @VisibleForTesting

chrome/android/java/src/org/chromium/chrome/browser/download/DownloadNotificationService2.java

@@ -320,16 +320,16 @@ public class DownloadNotificationService2 {
         Notification notification = DownloadNotificationFactory.buildNotification(
                 context, DownloadNotificationFactory.DownloadStatus.PAUSED, downloadUpdate);
 
-        updateNotification(notificationId, notification, id,
-                new DownloadSharedPreferenceEntry(id, notificationId, isOffTheRecord,
-                        canDownloadWhileMetered, fileName, isAutoResumable, isTransient));
-
         // If called from DownloadBroadcastManager, only update notification, not tracking.
         if (hasUserGesture) {
             updateNotification(notificationId, notification);
             return;
         }
 
+        updateNotification(notificationId, notification, id,
+                new DownloadSharedPreferenceEntry(id, notificationId, isOffTheRecord,
+                        canDownloadWhileMetered, fileName, isAutoResumable, isTransient));
+
         mDownloadForegroundServiceManager.updateDownloadStatus(context,
                 DownloadForegroundServiceManager.DownloadStatus.PAUSE, notificationId,
                 notification);