End TreeBuilder's reliance on DOM.
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Fixed h5e's TreeBuilder so that it does not use `same_tree` and `has_parent_node` methods: d8c2ea5cb6
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The alias is left there temporarilly and will be removed completely in a later commit where
also components/style/gecko/generated/structs_{debug|release}.rs are re-generated (they still
use the old alias).
Issue #15017: Properly handle and report network errors on page loads.
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This patch fixes how network errors are handled during page loads: they would not be reported and cause crashes before, and do not anymore.
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- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix#15017 (github issue number if applicable).
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Use the newly stored line as the starting line number when
evaluating JS. This ensures that inline scripts will report
errors with meaningful line numbers.
If the last child of a node is a Text child and we are inserting text in that node,
we need to append it to that Text child. Doing that means that
HTMLStyleElement::children_changed gets called less frequently, but that's not a
problem during parsing thanks to the pop hook.
It could be used to have mutable JSVal fields without GC barriers.
With the removal of that trait, MutHeap and MutNullableHeap can respectively
be replaced by MutJS and MutNullableJS.
