[css-lists] Import Mozilla's css-lists reftests

Bug: 687946
Change-Id: Ia198f20b0640a2d4ee5fe0be6448be5fcc492683
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1844999Reviewed-by: Manuel Rego <rego@igalia.com>
Commit-Queue: Manuel Rego <rego@igalia.com>
Cr-Commit-Position: refs/heads/master@{#703435}

third_party/blink/web_tests/W3CImportExpectations

@@ -100,7 +100,6 @@ external/wpt/css/vendor-imports/mozilla/mozilla-central-reftests/css21 [ Skip ]
 external/wpt/css/vendor-imports/mozilla/mozilla-central-reftests/filters [ Skip ]
 external/wpt/css/vendor-imports/mozilla/mozilla-central-reftests/fonts3 [ Skip ]
 external/wpt/css/vendor-imports/mozilla/mozilla-central-reftests/images3 [ Skip ]
-external/wpt/css/vendor-imports/mozilla/mozilla-central-reftests/lists-3 [ Skip ]
 external/wpt/css/vendor-imports/mozilla/mozilla-central-reftests/masking [ Skip ]
 external/wpt/css/vendor-imports/mozilla/mozilla-central-reftests/multicol3 [ Skip ]
 external/wpt/css/vendor-imports/mozilla/mozilla-central-reftests/ruby [ Skip ]