Import web-platform-tests@88b9a65ce806b5f67e0a535bf2f1602c2df6af58

Using update-w3c-deps in Blink e0d60fbe0459693abc293f4093ed802513855b29.

- Old custom-elements tests are moved to "pre-v1" directory.

- New failures due to spec changes.
dom/lists/DOMTokenList-coverege-for-attributes.html
html/semantics/interfaces.html

- Starts failing by "improve test stability" fixes in
https://github.com/w3c/web-platform-tests/pull/2937
dom/nodes/Document-contentType/contentType/contenttype_javascripturi.html

- Several files addded [ Skip ] since they require external files.
html/dom/dynamic-markup-insertion/opening-the-input-stream/004.html

[email protected], [email protected], [email protected]

Review-Url: https://codereview.chromium.org/1949503002
Cr-Commit-Position: refs/heads/master@{#391444}
110 files changed