1145017 - Use our new binding proto setup for custom element prototypes when possible

Status: RESOLVED FIXED

(Core :: DOM: Core & HTML, defect)

Description

[Boris Zbarsky [:bzbarsky]]

The patch checked in for bug 1130028 seems to rely on post-wrapping SetPrototype calls, and in particular on the prototype set happening on the Xray, not on the object itself.

This, unfortunately, does not play nice at all with what I was trying to do in the "part 4" patch in bug 1117172.

The reason I'd like to do _something_ there is that in the common case of all the stuff being part of the webpage we don't want to do the dynamic JS_SetPrototype business: that deoptimizes the object and makes performance-me very unhappy.

Seems to me like if NodePrincipal() subsumes the compartment principal of the proto we should be able to just pass it in as-is.  Otherwise, do what we do now.  Seem reasonable?

Comment 1

[Boris Zbarsky [:bzbarsky]]

Attachment: Use the new proto setup for custom element prototypes when possible

Note that with this patch I'm also changing the priority order of the given
proto and the custom proto; the former takes priority.  This makes sense to me:
if the caller is doing |new Foo| they really should get something with
Foo.prototype as its proto.  This should not be a problem for custom elements
in general so far, because nodes/elements are mostly not constructible anyway.
For now.  When they become that way, I think this is the behavior we'll want.

Comment 2

[Boris Zbarsky [:bzbarsky]]

https://hg.mozilla.org/integration/mozilla-inbound/rev/6030e30ae43d

Comment 3

[Phil Ringnalda (:philor)]

https://hg.mozilla.org/mozilla-central/rev/6030e30ae43d