Unconstruct method if any type arguments are error types

[bmay2]

Fixes #1903

[Pilchie]

Tag @dotnet/roslyn-ide for review.

@dotnet-bot test vsi please.

[Pilchie]

@CyrusNajmabadi in particular might want to take a look at this.

[CyrusNajmabadi]

👍

[Pilchie]

Any chance this makes things worse in cases where some of the constructed arguments would have been better matches?

[CyrusNajmabadi]

Any chance this makes things worse

Really hard to say. We have a reasonably good test bed for type inference (both directly, and through lots of refactoring tests). That nothing even changed is a good sign.

[balajikris]

👍

[balajikris]

@Pilchie I'm ready to merge this in, if your concerns have eased?

[Pilchie]

Yes, let's go!

[balajikris]

@bmay2 thanks for the contribution.