Restarting a Debug Adapter doesn't reset the Visual Studio Interface

1) Create a debug adapter which supports restart by specifying `supportsRestartRequest`. 2) Stop at a breakpoint such that the Variables and Call Stack interfaces are populated 3) Press the Restart button in Visual Studio Code Expected: The Visual Studio Code interface is reset when it gets back the empty response from the Restart request message Actual: The Visual Studio Code interface remains stale after getting sent a response from the Restart request.