Revert the following PRs that introduced exactness on HeapType: - #7446 - #7444 - #7432 - #7412 - #7396 Keep only the changes to wasm-type-printing.cpp to fix the assertions that subclasses of TypeNameGeneratorBase correctly override getNames. Although putting exactness on heap types makes the most sense in the Custom Descriptors spec, it is not a great fit for how HeapType is used in Binaryen. In almost all cases, HeapType is used to represent heap type definitions rather than the dynamic types of values. Letting HeapType represent exact heap types is not useful in those cases and opens up a new class of possible bugs. To avoid these bugs, we had been introducing a new HeapTypeDef type to represent heap type definitions, but nearly all uses of HeapType would have had to have been replaced with HeapTypeDef. Rather than introduce HeapTypeDef as a third type alongside Type and HeapType, it will be simpler to continue using HeapType to represent heap type definitions and Type to represent the dynamic types of values, including their exactness. While exactness will syntactically be part of the heap type, it will be part of the `Type` in Binaryen IR. A follow-on PR will restore the original work on exact references, and PRs following that one will update the encoding, parsing, and printing of exact references to match the current spec.

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Commits on Apr 15, 2025

Revert exact HeapTypes