refactor(semantic): always use SymbolFlags::Function for function id

[Dunqing]

close #7402
related: #7470

The purpose of this PR is to keep the SymbolFlags of the function consistent.

Always use SymbolFlags::Function for the function id symbol, to avoid adding extra logic to find accurate SymbolFlags for the function in transformer. This change adds a fallback redeclaration check for case async function foo() {}; var foo; in SemanticBuilder::check_redeclaraion.

No performance difference here because redeclaration is always rare.

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[Dunqing]

• fix(transformer): correct function symbol flags to SymbolFlags::Function #10008
• refactor(semantic): always use SymbolFlags::Function for function id #7479 👈 (View in Graphite)
• main

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[codspeed-hq]

CodSpeed Instrumentation Performance Report

Merging #7479 will not alter performance

_{Comparing 11-26-refactor_semantic_keep_consistent_symbolflags_for_function_id (0fa58d7) with main (be62d38)}

Summary

✅ 28 untouched benchmarks
🆕 5 new benchmarks

Benchmarks breakdown

	Benchmark	BASE	HEAD	Change
🆕	lexer[RadixUIAdoptionSection.jsx]	N/A	21.2 µs	N/A
🆕	lexer[antd.js]	N/A	24.8 ms	N/A
🆕	lexer[cal.com.tsx]	N/A	5.9 ms	N/A
🆕	lexer[checker.ts]	N/A	14.8 ms	N/A
🆕	lexer[pdf.mjs]	N/A	3.9 ms	N/A

[Boshen]

Merge activity

• Nov 28, 5:54 AM EST: The merge label '0-merge' was detected. This PR will be added to the Graphite merge queue once it meets the requirements.
• Nov 29, 12:14 AM EST: Graphite disabled "merge when ready" on this PR due to: a merge conflict with the target branch; resolve the conflict and try again..
• Nov 29, 12:14 AM EST: The merge label '0-merge' was detected. This PR will be added to the Graphite merge queue once it meets the requirements.
• Mar 24, 4:50 AM EDT: A user added this pull request to the Graphite merge queue.
• Mar 24, 4:58 AM EDT: A user merged this pull request with the Graphite merge queue.

[overlookmotel]

Can we possibly discuss this before merging? Personally, I'm not convinced this is a good idea.

[Boshen]

oxc/crates/oxc_transformer/src/es2017/async_to_generator.rs

Lines 368 to 373 in 58a125f

	// TODO: Needs a better way to handle the function SymbolFlags in different ModuleKind.
	let flags = if self.ctx.source_type.is_module() && ctx.current_scope_flags().is_top() {
	SymbolFlags::BlockScopedVariable | SymbolFlags::Function
	} else {
	SymbolFlags::FunctionScopedVariable
	};