/// <summary>
 /// Called before this object is serialize by Unity.
 /// Stores the target and custom editor types as string.
 /// </summary>
 public void OnBeforeSerialize()
 {
     m_TargetTypeName       = TargetType.GetFullNameWithAssembly();
     m_CustomEditorTypeName = CustomEditorType.GetFullNameWithAssembly();
 }