Allow representing function component values

[NickGerleman]

Summary: CSS component values, as defined in the syntax spec, are either "preserved tokens", CSS functions, or simple blocks. This is distinct from the higher-level "component value type" specified in the values and units spec.

I was previously short-circuiting a bit, from preserved tokens, to a higher level data structure. This separates them out, adding a layer exposing the preserved token, and now a CSSParser::FunctionComponentValue, which can represent a named function and its nested component values.

This does not yet wire functions beyond CSSParser returned component values.

Changelog: [Internal]

Differential Revision: D57089275

[facebook-github-bot]

This pull request was exported from Phabricator. Differential Revision: D57089275

[facebook-github-bot]

This pull request was exported from Phabricator. Differential Revision: D57089275

[analysis-bot]

Platform	Engine	Arch	Size (bytes)	Diff
android	hermes	arm64-v8a	19,495,390	+11
android	hermes	armeabi-v7a	n/a	--
android	hermes	x86	n/a	--
android	hermes	x86_64	n/a	--
android	jsc	arm64-v8a	22,867,563	-9
android	jsc	armeabi-v7a	n/a	--
android	jsc	x86	n/a	--
android	jsc	x86_64	n/a	--

Base commit: deee037c62a7d62a349d34db427b14d3560ddf83 Branch: main

[facebook-github-bot]

This pull request has been merged in facebook/react-native@a37111a4dd6a603cc9f346713c90292f23b3685f.

[github-actions[bot]]

This pull request was successfully merged by @NickGerleman in a37111a4dd6a603cc9f346713c90292f23b3685f.

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