Add workaround for delegate stuck transition bug

Sometimes and randomly, a HListView/HGridView delegate's
add/populate transition will stop before completion.

This especially happens on startup when loading a large room list,
one room might get stuck and left tiny or invisible, despite its
normal space still being taken.

src/gui/Pages/Chat/RoomPane/MemberView/MemberDelegate.qml

@@ -171,4 +171,6 @@ HTile {
         value: (roomPane.minimumSize - avatar.width) / 2
         when: avatar && roomPane.width < avatar.width + theme.spacing * 2
     }
+
+    DelegateTransitionFixer {}
 }

src/gui/Pages/Chat/RoomPane/MemberView/MemberDeviceDelegate.qml

@@ -64,4 +64,6 @@ HTile {
         )
         item.trustSet.connect(deviceTile.trustSet)
     }
+
+    DelegateTransitionFixer {}
 }