Allow null conditional be left side

[ahdung]

I hope can do this:

obj?.Prop = xxx; // if obj == null, do nothing

[jnm2]

Me too. This is currently championed at #2883.

[bernd5]

Thanks - and nice idea

[ahdung]

@jnm2 my fault

[jnm2]

@ahdung Don't worry, it can be hard to know how to find existing issues.