Run same tests for layout-2020 and layout-2013 (#30092)

Most tests were only being run for layout-2013, not for layout-2020.
This wasn't great since layout-2020 is now the default.

So this patch unifies the lists of included tests for both layouts.
For layout-2013 this implies adding css/css-content/, css/css-logical/
and css/css-masking/clip/.
For layout-2020 this implies adding several additional css tests, and
also tests like dom/, js/, html/, etc.

tests/wpt/meta/css/selectors/is-where-basic.html.ini

@@ -1,5 +1,45 @@
 [is-where-basic.html]
-  expected: ERROR
   [:is() matches expected elements]
     expected: FAIL
 
+  [:is(#a) matches expected elements]
+    expected: FAIL
+
+  [:is(#a, #f) matches expected elements]
+    expected: FAIL
+
+  [:is(#a, #c) :where(#a #d, #c #f) matches expected elements]
+    expected: FAIL
+
+  [#c > :is(#c > #f) matches expected elements]
+    expected: FAIL
+
+  [#c > :is(#b > #f) matches expected elements]
+    expected: FAIL
+
+  [#a div:is(#d) matches expected elements]
+    expected: FAIL
+
+  [:is(div) > div matches expected elements]
+    expected: FAIL
+
+  [:is(*) > div matches expected elements]
+    expected: FAIL
+
+  [:is(*) div matches expected elements]
+    expected: FAIL
+
+  [div > :where(#e, #f) matches expected elements]
+    expected: FAIL
+
+  [div > :where(*) matches expected elements]
+    expected: FAIL
+
+  [:is(*) > :where(*) matches expected elements]
+    expected: FAIL
+
+  [:is(#a + #b) + :is(#c) matches expected elements]
+    expected: FAIL
+
+  [:is(#a, #b) + div matches expected elements]
+    expected: FAIL