[webcomponents] shadow assets improved for a11y (#339)

One SVG, only half-finished improving… (but better than the version
already merged)

Keeping in a parallel directory as protection against having it
overwritten (I hope)
You can view, comment on, or merge this pull request online at:

  https://github.com/w3c/webcomponents/pull/339

-- Commit Summary --

  * shadow assets improved for a11y

-- File Changes --

    A assets/a11y/composed-tree.svg (101)

-- Patch Links --

https://github.com/w3c/webcomponents/pull/339.patch
https://github.com/w3c/webcomponents/pull/339.diff

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Reply to this email directly or view it on GitHub:
https://github.com/w3c/webcomponents/pull/339