servo: Merge #18056 - End TreeBuilder's reliance on DOM (from cynicaldevil:remove-treesink-dep-on-dom); r=nox

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Fixed h5e's TreeBuilder so that it does not use `same_tree` and `has_parent_node` methods: https://github.com/cynicaldevil/html5ever/commit/d8c2ea5cb62a1a755bb78b9f5de05d966776883a
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Source-Repo: https://github.com/servo/servo
Source-Revision: 62d0de349debf54c32e865e813eac43fb83df7be

--HG--
extra : subtree_source : https%3A//hg.mozilla.org/projects/converted-servo-linear
extra : subtree_revision : 253819d3fda84fac003101f132bd629f93aa3fa8