对象，用于解析对 ExposedReference 字段的引用。
ExposedReference 字段使用此对象在运行时解析它们的值。
See also:
• FrameData – You can find the ExposedPropertyResolver as a member of the FrameData structure you receive in Playable.PrepareFrame
• ExposedReference – You pass the ExposedPropertyResolver to the Resolve method to get the value at runtime.