Array Destructuring APIs

[tustvold]

Is your feature request related to a problem or challenge? Please describe what you are trying to do.

As part of #1799 strongly typed ArrayData abstractions were added that allow constructing arrays from their constituent parts, and destructuring arrays back into their parts. Whilst it looks like we won't be moving ahead with a strongly typed ArrayData abstraction, these APIs are powerful and should be ported across to the corresponding Array implementation.

Describe the solution you'd like

Each of the various Array should have:

• An unsafe new_unchecked that constructs it from raw ScalarBuffer, OffsetBuffer, etc...
• A safe try_new method that performs validation and returns a Result
• An into_parts method that returns the constituent parts that can be fed to new_unchecked
• Methods should return &ScalarBuffer<T>, &BooleanBuffer, etc... instead of &[T], &[u8] etc...

Describe alternatives you've considered

Additional context

[jhorstmann]

Would the into_parts method consume the array and return owned buffers? I think this could avoid some Arc clones for commons usecases.

[alamb]

I wonder if this issue is complete now

[tustvold]

I think it is just some of the more esoteric arrays that need constructors, like FixedSizeBinary. I will try to find time to get this over the line soon