[dom] Fix the set an attribute algorithm (#139)

Only one mutation record should be queued, according to both WebKit and Gecko.
You can view, comment on, or merge this pull request online at:

  https://github.com/whatwg/dom/pull/139

-- Commit Summary --

  * Fix the set an attribute algorithm

-- File Changes --

    M dom.bs (30)
    M dom.html (21)

-- Patch Links --

https://github.com/whatwg/dom/pull/139.patch
https://github.com/whatwg/dom/pull/139.diff

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Reply to this email directly or view it on GitHub:
https://github.com/whatwg/dom/pull/139