Remove ISchematized interface from the codebase.

[wschin]

1. Remove ISchematized
2. For any class that requires a Schema, we add a Schema as its field
3. Rename Schema to OutputSchema in IRowToRowMapper

Fixes #1502.

[TomFinley]

Schema Schema [](start = 24, length = 13)

We might want to hide this Schema behind an explicit interface implementation, e.g., IDataView.Schema or somesuch, since we don't want to emphasize the fact that this is an IDataView (it eventually will not be). The base class, whatever it is, could have a IDataView.Schema that references a [BestFriend] private protected abstract Schema DataSchema that is overridden here and elsewhere, if appropriate. Then people won't get these identical Schema and OutputSchema in their face, and it also clears the way to more easily deprecate the fact that this is also an IDataTransform in the future. #Resolved

[wschin]

Thank you Tom! In TransformBase (where IDataTransform is inherited), we have

        Schema IDataView.Schema => OutputSchema;
        public abstract Schema OutputSchema { get; }

for hidding IDataView.Schema. Do we still need [BestFriend] private protected abstract Schema DataSchema?

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In reply to: 237585047 [](ancestors = 237585047)

[Ivanidzo4ka]

You have changes in libmf submodule, is it necessary? #Resolved

[wschin]

It's not! It's my turn making this mistake. Let me fix it.

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In reply to: 443316147 [](ancestors = 443316147)

[TomFinley]

Thanks for getting rid of this @wschin !

[wschin]

Fixing this problem is difficult because git automatically fetches the latest commit for the tracked branch. If you don't mind, let's just keep these changes.
[Update] It turnes out that it's a bug on Github. If you check the build log, we're still using the correct commit.

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In reply to: 443316482 [](ancestors = 443316482,443316147)

[Ivanidzo4ka]