Now that XBL scopes are here to stay (no more pref), we can remove all the
machinery that makes SOWs dynamic. We still need SOWs until bug 825392 is
fixed, but they can now be totally opaque.
One side effect of this patch is that, due to our usage of Opaque, we now
allow CALL on SOWs. But this shouldn't be a problem, because SOWs are used
for anonymous elements which are not callable (and we probably wouldn't mind
it even if they were).
We have to do this if we want to proceed with eliminating SOWs entirely. Given
the other restrictions around remote XUL, I don't think this is a problem.
Note that we shouldn't need any special handling in the wrapper reparenting
paths, because those all depend on whether a SOW was there already. So that
would only be an issue if it were possible to adoptNode from a non-remote-XUL
domain into a remote-XUL domain, which thankfully can't happen.
There are several changes here:
1) Adds some MutableThis methods to Optional, Nullable, and dictionaries to
effectively allow doing a const_cast without knowing the actual type being
templated over. I needed this because I do not in fact know that type in
the relevant code. I'm open to suggestions for a better name for this
method.
2) Adds some operator& to RootedJSValue to make it look more like a JS::Value,
and in particular so I can JS_WrapValue the thing in it.
3) Adds a Slot() method to NonNullLazyRootedObject, just like NonNull has.
4) Adds an operator& to LazyRootedObject to make it look more like JSObject* so
I can JS_WrapObject the thing in it.
5) Implements the actual rewrapping of the arguments into the content compartment.
6) Fixes a small preexisting bug in which we didn't look at named constructors
in getTypesFromDescriptor (this was causing my tests to not compile).
7) Changes Xrays to not enter the content compartment when calling a WebIDL
constructor.
8) Adds some friend API to report things as not being functions.
Right now, it sometimes fills out |desc|, and sometimes just defines the property
on the holder. This can get confusing, so let's refine the semantics here and
describe them in a big comment.
The current setup is just an artifact of how it used to be before I refactored
Xrays. Have it as a virtual trap is more flexible since it allows us to invoke
the right trap by just calling GetXrayTraits(wrapper) from non-templatized code.
