mock.SetupProperty throws NullReferenceException when called for partially overridden property

[stakx]

Noticed while working on a bug fix for #886 that SetupProperty will also fail for partially overridden properties, albeit for different reasons.

Steps to reproduce:

public class WithAutoProperty
{
    public virtual object Property { get; set; }
}

public class OverridesOnlySetter : WithAutoProperty
{
    public override object Property { set => base.Property = value; }
}

[Fact]
public void SetupAllProperties_retains_value_of_derived_read_write_property_that_overrides_only_setter()
{
    var mock = new Mock<OverridesOnlySetter>();
    mock.SetupProperty(m => m.Property);
    mock.Object.Property = "value";
    Assert.Equal("value", mock.Object.Property);
}

Expected outcome:

The test passes.

Actual outcome:

System.NullReferenceException : Object reference not set to an instance of an object.
   at Moq.ExpressionExtensions.GetReboundProperty(MemberExpression expression) in src\Moq\ExpressionExtensions.cs:line 327
   at Moq.ExpressionExtensions.ToPropertyInfo(LambdaExpression expression) in src\Moq\ExpressionExtensions.cs:line 343
   at Moq.Mock`1.SetupProperty[TProperty](Expression`1 property, TProperty initialValue) in src\Moq\Mock.Generic.cs:line 659
   at Moq.Mock`1.SetupProperty[TProperty](Expression`1 property) in src\Moq\Mock.Generic.cs:line 621
   at ...