We can only borrow JS<T> from rooted things, so it's safe to deref it.
The only types that provide mutable JS<T> things are MutHeap<JS<T>> and
MutNullableHeap<JS<T>>, which don't actually expose that they contain
JS<T> values.
added spec link for type mapping
Hi. added some of the spec links, that i could understand from the spec. Please mention if anything else needs to be added.
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Fix uses of JS<T> as a type on the stack
`JS<T>` belongs on the heap, and only on the heap. This is a collection of fixes so that code uses either `Root<T>` or `&T` to pass around garbage-collected pointers.
Ideally, we could completely ban constructing a `JS<T>` outside of constructor functions, but we aren't quite there yet.
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get() must always return a rooted value, because we have no way of
ensuring the value won't be invalidated. set() takes an &T because it's
convenient; there isn't any need to expose JS<T>.
Given codegen now generates the various TypeId enums, it seems pointless to
still have to write their respective values in every DOM struct inheriting from
Node just to set the initial IS_IN_DOC flag in Document and IN_ENABLED_STATE in
form controls.
Introduce DOMClass::heap_size_of
It holds a function pointer to the HeapSizeOf::heap_size_of_children()
implementation corresponding to that IDL interface.
This removes the need for a clumsly TypeId-based match expression in the
former heap_size_of_eventtarget() function.
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It holds a function pointer to the HeapSizeOf::heap_size_of_children()
implementation corresponding to that IDL interface.
This removes the need for a clumsly TypeId-based match expression in the
former heap_size_of_eventtarget() function.
