[C++][Dataset][Compute] Refactor Dataset scans to use an ExecNode graph

[asfimport]

Per discussion on https://docs.google.com/document/d/1AyTdLU-RxA-Gsb9EsYnrQrmqPMOYMfPlWwxRi1Is1tQ

Once Datasets can be streamed from efficiently (ARROW-7001), they can be wrapped in ScanNodes which push scanned batches into an ExecNode graph.

Filtering and Projection should then be handled by subsequent nodes in that graph.

Reporter: Ben Kietzman / @bkietz
Assignee: Ben Kietzman / @bkietz

Related issues:

• [C++] C++ array kernels framework and execution buildout (umbrella issue) (is a child of)
• [C++] Query engine umbrella issue (is a child of)

PRs and other links:

• GitHub Pull Request #10397

_{Note: This issue was originally created as ARROW-11930. Please see the migration documentation for further details.}

[asfimport]

Ben Kietzman / @bkietz:
Issue resolved by pull request 10397
#10397