A generic voxel listener is getting serialized. [fairly common]

[mklingen]

https://sentry.io/cfg/dwarfcorp/issues/874123246/?referrer=github_plugin

TargetInvocationException: Exception has been thrown by the target of an invocation.
  Module "Newtonsoft.Json.Serialization.JsonContract+<>c__DisplayClass73_0", line 0, in CreateSerializationCallback { <lambda> }
    Void <CreateSerializationCallback>b__0(System.Object, System.Runtime.Serialization.StreamingContext)
  Module "Newtonsoft.Json.Serialization.JsonContract", line 22, in InvokeOnSerializing
    Void InvokeOnSerializing(System.Object, System.Runtime.Serialization.StreamingContext)
  Module "Newtonsoft.Json.Serialization.JsonSerializerInternalWriter", line 68, in OnSerializing
    Void OnSerializing(Newtonsoft.Json.JsonWriter, Newtonsoft.Json.Serialization.JsonContract, System.Object)
  Module "Newtonsoft.Json.Serialization.JsonSerializerInternalWriter", line 0, in SerializeObject
    Void SerializeObject(Newtonsoft.Json.JsonWriter, System.Object, Newtonsoft.Json.Serialization.JsonObjectContract, Newtonsoft.Json.Serialization.JsonProperty, Newtonsoft.Json.Serialization.JsonContainerContract, Newtonsoft.Json.Serialization.JsonProperty)
  Module "Newtonsoft.Json.Serialization.JsonSerializerInternalWriter", line 176, in SerializeValue
    Void SerializeValue(Newtonsoft.Json.JsonWriter, System.Object, Newtonsoft.Json.Serialization.JsonContract, Newtonsoft.Json.Serialization.JsonProperty, Newtonsoft.Json.Serialization.JsonContainerContract, Newtonsoft.Json.Serialization.JsonProperty)
...
(30 additional frame(s) were not displayed)

InvalidProgramException: DO NOT SERIALIZE GENERIC VOXEL LISTENERS
  File "C:\Users\matth\Desktop\dwarfcorp\DwarfCorp\DwarfCorpXNA\Components\GenericVoxelListener.cs", line 51, in Serializer
    Void Serializer(System.Runtime.Serialization.StreamingContext)

Exception has been thrown by the target of an invocation.

[mklingen]

So this could be anywhere that a list of bodies is being serialized. Suggest an audit of such cases, especially when we're dealing with octree lookups, as generic voxel listener will sometimes end up in those searches.

[mklingen]

Added checks to ensure that fire only cares about root objects.