[List] Memoize context value

[mkermani144]

• I have followed (at least) the PR section of the contributing guide.

Related to #10778

Memoizing context value is another solution to https://reactjs.org/docs/context.html#caveats

[eps1lon]

There's currently an issue with shallow rendering + forwardRef + hooks. We need to adjust our test. I have prepared something locally which also improves this test as a whole unless you insist on doing this yourself.

The implementation is fine as-is.

[mui-pr-bot]

Details of bundle changes.

Comparing: 02b6dab...7e18acd

bundle	parsed diff	gzip diff	prev parsed	current parsed	prev gzip	current gzip
@material-ui/core	+0.01% 🔺	+0.02% 🔺	357,579	357,618	91,073	91,093
@material-ui/core/Paper	0.00%	0.00%	68,634	68,634	19,979	19,979
@material-ui/core/Paper.esm	0.00%	0.00%	62,366	62,366	19,060	19,060
@material-ui/core/Popper	0.00%	0.00%	30,454	30,454	10,525	10,525
@material-ui/core/styles/createMuiTheme	0.00%	0.00%	17,390	17,390	5,730	5,730
@material-ui/core/useMediaQuery	0.00%	0.00%	2,471	2,471	1,042	1,042
@material-ui/lab	0.00%	0.00%	152,165	152,165	44,548	44,548
@material-ui/styles	0.00%	0.00%	53,839	53,839	15,566	15,566
@material-ui/system	0.00%	0.00%	17,143	17,143	4,522	4,522
Button	0.00%	0.00%	90,924	90,924	26,941	26,941
Modal	0.00%	0.00%	84,711	84,711	25,208	25,208
colorManipulator	0.00%	0.00%	3,234	3,234	1,301	1,301
docs.landing	0.00%	0.00%	51,843	51,843	11,349	11,349
docs.main	+0.01% 🔺	+0.01% 🔺	649,999	650,044	201,578	201,596
packages/material-ui/build/umd/material-ui.production.min.js	+0.01% 🔺	+0.02% 🔺	305,844	305,881	83,862	83,876

Generated by 🚫 dangerJS against 7e18acd

[oliviertassinari]

@mkermani144 It's a great first pull request on Material-UI 👌🏻. Thank you for working on it!

[henrylearn2rock]

Any chance of merging to 3.9.x? Thanks

[ryancogswell]

Any chance of merging to 3.9.x?

@henrylearn2rock Sorry, but that won't be possible since the solution requires the useMemo hook, and 3.9.x doesn't require a version of React that supports hooks.

[oliviertassinari]

@henrylearn2rock v4.0.0-beta.0 is in good shape. You should be able to migrate, starting today. If you want to be more cautious, you can wait a week or two.