[Flight] Always initialize a debug info array for each Chunk

[sebmarkbage]

I'm about to add info for pretty much all of these anyway since they all depend on the data stream itself.

[react-sizebot]

Comparing: 3fb190f...520a61a

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.js	=	6.68 kB	6.68 kB	=	1.83 kB	1.83 kB
oss-stable/react-dom/cjs/react-dom-client.production.js	=	530.65 kB	530.65 kB	=	93.49 kB	93.49 kB
oss-experimental/react-dom/cjs/react-dom.production.js	=	6.69 kB	6.69 kB	=	1.83 kB	1.83 kB
oss-experimental/react-dom/cjs/react-dom-client.production.js	=	658.12 kB	658.12 kB	=	115.77 kB	115.77 kB
facebook-www/ReactDOM-prod.classic.js	=	682.25 kB	682.25 kB	=	119.80 kB	119.80 kB
facebook-www/ReactDOM-prod.modern.js	=	672.68 kB	672.68 kB	=	118.11 kB	118.11 kB

Significant size changes

Includes any change greater than 0.2%:

(No significant changes)

Generated by 🚫 dangerJS against 520a61a