This is an editorial change in the ECMA-402 spec. See:
a2beb66
We implement this change by introducing a virtual interface that all
Intl "service" objects must implement. A future patch will make use of
the virtualized RelevantExtensionKeys and ResolutionOptionDescriptors
accessors, and we will need to be able to use those slots from a generic
instance type.
The Duration record no longer exists in Temporal. Implement it according
to the DurationFormat spec to prepare for its removal from our Temporal
implementation.
We also implement the DurationSign AO here as well, as the Temporal
implementation will now require a Temporal.Duration JS object.
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