Download infobar : Removing a download should remove infobar

When a download is removed (e.g. via download home), we should
remove if we are showing an infobar for this download. Fixing
this bug in this CL.

Bug: 849407
Change-Id: I512d0a3e946b9c349badfaad9f304985678fd603
Reviewed-on: https://chromium-review.googlesource.com/1086286Reviewed-by: David Trainor <dtrainor@chromium.org>
Commit-Queue: Shakti Sahu <shaktisahu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#564783}

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

@@ -311,7 +311,7 @@ public class DownloadInfoBarController implements OfflineContentProvider.Observe
 
     @Override
     public void onItemRemoved(ContentId id) {
-        if (!mTrackedItems.containsKey(id)) return;
+        if (!mSeenItems.contains(id)) return;
 
         mTrackedItems.remove(id);
         mNotificationIds.remove(id);