[vmservices] NPE in `io.flutter.vmService.DisplayRefreshRateManager`

[pq]

On launching a web app,

2025-05-01 10:52:28,041 [ 144861]   WARN - #io.flutter.vmService.DisplayRefreshRateManager - java.lang.NullPointerException: Cannot invoke "com.google.gson.JsonElement.getAsString()" because the return value of "com.google.gson.JsonObject.get(String)" is null

[pq]

On a bit of poking, this may be percolating up from io.flutter.vmService.VMServiceManager#getFlutterViewId (which wouldn't be surprising since there's lots of JSON unmarshalling that isn't guarded).