Make enableNewBooleanProps www dynamic

[eps1lon]

Feature: #24730

[react-sizebot]

Comparing: 9ffe910...89f9f30

Critical size changes

Includes critical production bundles, as well as any change greater than 2%:

Name	+/-	Base	Current	+/- gzip	Base gzip	Current gzip
oss-stable/react-dom/cjs/react-dom.production.min.js	=	176.83 kB	176.83 kB	=	54.91 kB	54.91 kB
oss-experimental/react-dom/cjs/react-dom.production.min.js	=	173.55 kB	173.55 kB	=	54.11 kB	54.11 kB
facebook-www/ReactDOM-prod.classic.js	+0.02%	594.04 kB	594.16 kB	+0.04%	104.37 kB	104.42 kB
facebook-www/ReactDOM-prod.modern.js	+0.02%	577.30 kB	577.42 kB	+0.03%	101.42 kB	101.45 kB
test_utils/ReactAllWarnings.js	Deleted	66.87 kB	0.00 kB	Deleted	16.36 kB	0.00 kB

Significant size changes

Includes any change greater than 0.2%:

Expand to show

Name	+/-	Base	Current	+/- gzip	Base gzip	Current gzip
facebook-www/ReactDOMServerStreaming-dev.modern.js	+0.35%	486.24 kB	487.97 kB	+0.32%	98.74 kB	99.05 kB
facebook-www/ReactDOMServer-dev.modern.js	+0.35%	493.47 kB	495.19 kB	+0.31%	100.36 kB	100.67 kB
facebook-www/ReactDOMServer-dev.classic.js	+0.35%	496.05 kB	497.77 kB	+0.32%	100.85 kB	101.17 kB
test_utils/ReactAllWarnings.js	Deleted	66.87 kB	0.00 kB	Deleted	16.36 kB	0.00 kB

Generated by 🚫 dangerJS against 89f9f30

[eps1lon]

@jackpope Do you merge it and take care of rolling it out internally?

[jackpope]

@eps1lon Yes I can handle. Thanks for setting up the dynamic flag!