Fix NotificationStackScrollLayoutController#getVisibleNotificationCount() == 0

Fixes: 208229469
Test: manual/logging
Change-Id: Id1e2387f76a77eab69c79d9e5df1952ee92dd2e2

packages/SystemUI/src/com/android/systemui/statusbar/NotificationViewHierarchyManager.java

@@ -368,6 +368,7 @@ public class NotificationViewHierarchyManager implements DynamicPrivacyControlle
             // NOTE: NotificationEntry.isClearable() will internally check group children to ensure
             //  the group itself definitively clearable.
             boolean isClearable = row.getEntry().isClearable();
+            visibleTopLevelEntries++;
             if (isSilent) {
                 if (isClearable) {
                     hasClearableSilentNotifs = true;