Replace return_address usage for rooting with stack guards and convenience macros.
The existing `Rooted` and `RootedVec` users were migrated the the following two macros:
```rust
let x = Rooted::new(cx, value);
// Was changed to:
rooted!(in(cx) let x = value);
// Which expands to:
let mut __root = Rooted::new_unrooted(value);
let x = RootedGuard::new(cx, &mut __root);
```
```rust
let mut v = RootedVec::new();
v.extend(iterator);
// Was changed to:
rooted_vec!(let v <- iterator);
// Which expands to:
let mut __root = RootableVec::new();
let v = RootedVec::new(&mut __root, iterator);
```
The `rooted!` macro depends on servo/rust-mozjs#272.
These APIs based on two types, a container to be rooted and a rooting guard, allow implementing both `Rooted`-style rooting and `Traceable`-based rooting in stable Rust, without abusing `return_address`.
Such macros may have been tried before, but in 1.9 their hygiene is broken, they work only since 1.10.
Sadly, `Rooted` is a FFI type and completely exposed, so I cannot prevent anyone from creating their own, although all fields but the value get overwritten by `RootedGuard::new` anyway.
`RootableVec` OTOH is *guaranteed* to be empty when not rooted, which makes it harmless AFAICT.
By fixing rust-lang/rust#34227, this PR enables Servo to build with `-Zorbit`.
---
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fixrust-lang/rust#34227
- [x] These changes do not require tests because they are not functional changes
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It's now set through the intermediate InterfaceConstructorBehavior structure,
which lets us improve the abstraction around NonCallbackInterfaceObjectClass
a bit better.
When the interface's constructor is supposed to always throw, the error for
calling `Foo()` without new is "Illegal constructor.". when the interface
actually defines an interface, the error is instead
"This constructor needs to be called with `new`.".
Fixed compile error in generated code, when webidl constructors have same number of args
One of the ways that generated code differentiates constructors is by comparing if the args are array-like. The generated code was calling a function `IsArrayLike` that no longer exists. I re-implemented it with a more rust-like naming scheme.
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According to JSProxy.h, without this the default implementation calls
ownPropertyKeys and filters out the unenumerable properties. We know when such
things exist so we don't need to do that.
