Enable more css tests (#31469)

* Enable more css tests

In particular, these directories are no longer skipped:
 - CSS1 (has no tests)
 - css-box (except margin-trim)
 - css-cascade
 - css-display (except run-in)
 - css-easing
 - css-env
 - css-lists
 - css-namespaces
 - css-overflow
 - css-pseudo
 - css-sizing (except aspect-ratio and contain-intrinsic-size)
 - css-syntax
 - reference
 - support (has no tests)

* Sort list properly

* Explicitly list skipped directories

* Do not skip css tests by default

* Add expectations

tests/wpt/meta/css/css-syntax/var-with-blocks.html.ini

@@ -0,0 +1,42 @@
+[var-with-blocks.html]
+  [Plain var()]
+    expected: FAIL
+
+  [Whole-value block with var()]
+    expected: FAIL
+
+  [Whole-value block with var() (spaces)]
+    expected: FAIL
+
+  [Trailing block, leading var()]
+    expected: FAIL
+
+  [Leading block, trailing var()]
+    expected: FAIL
+
+  [In-block var() with trailing token]
+    expected: FAIL
+
+  [In-block var() with leading token]
+    expected: FAIL
+
+  [Plain var() (custom property)]
+    expected: FAIL
+
+  [Whole-value block with var() (custom property)]
+    expected: FAIL
+
+  [Whole-value block with var() (spaces, custom property)]
+    expected: FAIL
+
+  [Trailing block, leading var() (custom property)]
+    expected: FAIL
+
+  [Leading block, trailing var() (custom property)]
+    expected: FAIL
+
+  [In-block var() with trailing token (custom property)]
+    expected: FAIL
+
+  [In-block var() with leading token (custom property)]
+    expected: FAIL