[flexiglass] Fix remote touch on flexiglass over launcher

Since flexiglass no longer consumes touches on the whole screen when we are idle on the Gone scene, we need to use the existing RemoteUserInteractionOngoing state to allow us to consume the expansion gesture when over launcher.

Bug: 347699508
Test: Manually verified Gone -> Shade gesture works as expected
Test: Manually verified RemoteUserInteractionOngoing value in TouchableRegionManager is correct throughout the gesture via logging
Flag: com.android.systemui.scene_container
Change-Id: I0e9effc5ccae5e7615570713d968b281ba0ca306