处理 nullable GetValueOrDefault

[leinlin]

nullable的值直接进行比较的时候，会将取值函数更改为GetValueOrDefault，injectfix就会报错

[tencent-adm]

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[leinlin]

throw new TargetException(string.Format("can not invoke method [{0}.{1}], Non-static method require instance but got null.", method.DeclaringType, method.Name));