Incorporate feedback comments raised while open sourcing System.IO.IsolatedStorage

[pallavit]

Fixes Issue#4954

[pallavit]

@stephentoub Could you please review the change.
@dsgouda It might be a good idea to consider updating instance members from m_ to _ and converting Contract.Assert to Debug.Assert() across all libraries while open sourcing, since these will be common across the board.

[mellinoe]

Assuming we aren't using anything from Contracts anymore, this can be removed

[weshaggard]

Yes please sort and remove unused. We should make CodeFormatter tool do that :)

[pallavit]

We are using Contract via Contract.EndContractBlock and PureAttribute :)

[mellinoe]

Okay, sounds good to me. How do we feel about removing the EndContractBlock calls? I thought those were only useful if we were using Code Contracts.

[pallavit]

In my personal opinion, they are not very useful, however, its merits are still under debate (#503 , dotnet/corert#320, dotnet/roslyn#98) and I do see other libraries relying on it. So for now, I don't see any harm in letting them stay.

[weshaggard]

Agreed I've held back on doing a scrub of all the contract calls for now until we figure out our longer term story around them.

[mellinoe]

A minor nit, otherwise LGTM

[weshaggard]

LGTM otherwise.

[pallavit]

Thanks for the review merging the changes.