[Dual Shade] Show icon and text in EmptyShadeView

I opted for forking EmptyShadeView and status_bar_no_notifications.xml
since we're changing 90% of the view anyway, so I find it cleaner than
flagging off every single piece of the old view.

Fix: 388472403
Fix: 439537988
Test: EmptyShadeViewModelTest
Flag: com.android.systemui.show_icon_in_empty_shade

Change-Id: I89d24e418297ff17c93d54dafa8d3f090ff2cb06