Fixes the bug that @alexmckenley and @mofeiZ found where setState-in-render can reset useMemoCache and cause an infinite loop. The bug was that renderWithHooksAgain() was not resetting hook state when rerendering (so useMemo values were preserved) but was resetting the updateQueue. This meant that the entire memo cache was cleared on a setState-in-render.
The fix here is to call a new helper function to clear the update queue. It nulls out other properties, but for memoCache it just sets the index back to zero.
ghstack-source-id: fc0947ce21
Pull Request resolved: https://github.com/facebook/react/pull/30889
Joe Savona
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