Implement basic framework for static and interactive validation on forms
This came along when I was trying to do #3648. I was about to do form validation as well, but then I saw it was actually intended to be a student project. Hopefully I didn't step on too many toes on this one; I did leave most of the important bits out (the fun bits I believe, e.g. interactive validation doesn't actually interactively validate anything right now).
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Implement [Unforgeable]
This is mostly stolen from Gecko. As there, we define the unforgeable members
on an object stored in the slots of the prototype object. They are then copied
onto instance objects when they are instantiated. It should be noted that
proxy objects see their unforgeable memebers defined on their expando object.
Unforgeable attributes aren't properly inherited in codegen (in a similar
fashion as getters and setters as filed in #5875) and require to be redefined
in derived interfaces. Fortunately, there are currently no such interfaces.
No unforgeable members can be included into the TestBinding interfaces for good
measure because they are not compatible with setters.
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This is mostly stolen from Gecko. As there, we define the unforgeable members
on an object stored in the slots of the prototype object. They are then copied
onto instance objects when they are instantiated. It should be noted that
proxy objects see their unforgeable memebers defined on their expando object.
Unforgeable attributes aren't properly inherited in codegen (in a similar
fashion as getters and setters as filed in #5875) and require to be redefined
in derived interfaces. Fortunately, there are currently no such interfaces.
No unforgeable members can be included into the TestBinding interfaces for good
measure because they are not compatible with setters.
Given the unforgeable holder object has the same prototype as actual instances
of the interface, the finalize hook needs to check its slot pointer for nullity
before dropping it.
The new failing test isn't related to Unforgeable attributes, but to the fact
that all Document instances currently have a Location, even if their window
isn't in a browsing context.
This is just the result of running --manifest-update on master; not sure
how it got out of sync.
These tests currently timeout, so also add the expected result.
Simplify implementation of '<canvas>' 'width' and 'height' attributes.
Strictly speaking, this affects correctness for extremely large width and height values... but that's unlikely to matter in practice.
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