M1504: Implement final charset support for text_response method
Following changes have been made:
* Added final_mime_type and final_charset helper methods to return the appropriate final mime/charset values
* Modified the text_response method to use the final_charset instead of directly using the response charset
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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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These two tiny changes were making WebGL textures not work.
It was not seen in our texturing test since we render to a texture by
default, and that texture was bound to `gl::TEXTURE_2D`.
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.
There wasn't a good way to split this up, unfortunately.
With this change, the only remaining usage of the Servo-specific structures is
in layout_task, where the root node is received from the script task. \o/
If we use ThreadsafeLayoutNodeChildrenIterator directly as the return type of children(),
we need to export the DangerousThreadSafeLayoutNode which the iterator implementation
relies upon.
Build Fragments without the RECONSTRUCT_FLOW bit
The RECONSTRUCT_FLOW restyle damage bit shouldn't apply to newly
constructed flow tree elements. It is explicitly removed for Flows, but
not for Fragments. This causes RECONSTRUCT_FLOW to bubble up to Flows
that contain any Fragments at all. Instead explicitly remove the
RECONSTRUCT_FLOW bit when creating a new Fragment.
There isn't a good way to test this currently, but all tests should
continue to pass.
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