Previously we were inconsistent by generating code for enum definitions
but not generating code for dictionaries. With future changes to the
IDL generator to expose helpers to convert to and from IDL values
this produced circular depdendencies. To solve this problem, also
generate the dictionary definitions in bindings headers.
This now takes a registry directly. As a temporary stop-gap, the old
method on Document is still here and calls the new one.
We do get a test regression:
"Creating an element in a cloned document and inserting into the
document must not enqueue a custom element upgrade reaction" in
"custom-elements/upgrading.html".
Possibly a spec bug?
Resulting in a massive rename across almost everywhere! Alongside the
namespace change, we now have the following names:
* JS::NonnullGCPtr -> GC::Ref
* JS::GCPtr -> GC::Ptr
* JS::HeapFunction -> GC::Function
* JS::CellImpl -> GC::Cell
* JS::Handle -> GC::Root
