Remove memoization of buildMenuOptions

[Methuselah96]

Resolves #4259.
Alternative to #4349.

Background

Memoization of buildMenuOptions was added in #3868 as part of the 3.1.0 release. As noted in the PR:

I've made buildMenuOptions memoized, so that it does not run the function again if the props that the function uses didn't change.

and

I can remove the memoizing part to make the build pass, if that would speed up the merging and reviewing of this PR. It would be a bit more inefficient, but it would fix the bug.

Proposal

Reasons to remove the memoization:

1. The memoization was not essential to the fix in question.
2. It has since caused other issues including onCreateOption is not called, fails at valueArray[valueArray.length - 1] === newOption #3988 (already resolved) and isOptionDisabled does not update disabled items between renders #4259.
3. One of the values that would require buildMenuOptions to be recomputed is the inputValue prop. Since the inputValue prop is likely to change quickly, the memoization will not improve performance when the user is typing. Instead performance optimizations should be focused elsewhere.
4. The alternative is undesirable:
   a. There are a lot of props that are used in buildMenuOptions.
   b. Each of the functions now need to take the props as an argument because buildMenuOptions is used in componentWillReceiveProps.
   c. It would be easy to miss updating the list of props that are used in buildMenuOptions and it is not trivial to find all the props in use.

This would be included as part of the 4.0 release since there is a possible regression in performance. If the change proves to be undesirable, it should be easy to revert.

[changeset-bot]

🦋 Changeset detected

Latest commit: ff74140

The changes in this PR will be included in the next version bump.

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react-select	Patch

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Sandbox	Source
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little-glade-s2m9u	Issue #4259