Inherit JSFunction from JSClosure

[kateinoigakukun]

There is no reason not to make JSClosure to be compatible with JSFunction. We can treat JSClosure as a JSFunction and call it from not only JavaScript but also Swift.

[github-actions]

Time Change: +495ms (5%) 🔍

Total Time: 9,795ms

Test name	Duration	Change
Serialization/JavaScript function call through Wasm import	21ms	+2ms (11%)	⚠️
Serialization/JavaScript function call through Wasm import with int	15ms	+1ms	🔍
Serialization/JavaScript function call from Swift	102ms	+5ms (5%)	🔍
Serialization/Swift Int to JavaScript with assignment	342ms	+23ms (6%)	🔍
Serialization/Swift Int to JavaScript with call	1,008ms	+52ms (5%)	🔍
Serialization/JavaScript Number to Swift Int	312ms	+16ms (5%)	🔍
Serialization/JavaScript String to Swift String	3,838ms	+217ms (5%)	🔍

View Unchanged

Test name	Duration	Change
Serialization/Swift String to JavaScript with assignment	391ms	+15ms (3%)
Serialization/Swift String to JavaScript with call	1,059ms	+44ms (4%)
Object heap/Increment and decrement RC	2,694ms	+118ms (4%)

View Baselines

Test name	Duration
Serialization/Call JavaScript function directly	3ms
Serialization/Assign JavaScript number directly	3ms
Serialization/Call with JavaScript number directly	4ms
Serialization/Write JavaScript string directly	3ms
Serialization/Call with JavaScript string directly	3ms