dillon1000/react

validatePreserveExistingMemoizationGuarantees ensures compiler preserves subset of dependencies from source

--- 

`validatePreserveExistingMemoizationGuarantees` previously checked 

- manual memoization dependencies and declarations (the returned value) do not 
"lose" memoization due to inferred mutations 

``` 

function useFoo() { 

const y = {}; 

// bail out because we infer that y cannot be a dependency of x as its 
mutableRange 

// extends beyond 

const x = useMemo(() => maybeMutate(y), [y]); 

// similarly, bail out if we find that x or y are mutated here 

return x; 

} 

``` 

- manual memoization deps and decls do not get deopted due to hook calls 

``` 

function useBar() { 

const x = getArray(); 

useHook(); 

mutate(x); 

return useCallback(() => [x], [x]); 

} 

``` 

This PR updates `validatePreserveExistingMemoizationGuarantees` with the 
following correctness conditions: 

*major change* All inferred dependencies of reactive scopes between 
`StartMemoize` and `StopMemoize` instructions (e.g. scopes containing manual 
memoization code) must either: 

1. be produced from earlier within the same manual memoization block 

2. exactly match an element of depslist from source 

This assumes that the source codebase mostly follows the `exhaustive-deps` lint 
rule, which ensures that deps lists are (1) simple expressions composing of 
reads from named identifiers + property loads and (2) exactly match deps usages 
in the useMemo/useCallback itself. 

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Validated that this does not change source by running internally on ~50k files 
(no validation on `main`, no validation on this PR, and validation on this PR).