Bug 1918419: WPT tests for `position-try-fallbacks` should use canonical ordering. r=firefox-style-system-reviewers,emilio

Spec [1] defines "Canonical order: per grammar," so the serialization should
re-order `<try-tactics>` entries in order of their appearances [2].

[1]: https://drafts.csswg.org/css-anchor-position-1/#propdef-position-try-fallbacks
[2]: https://www.w3.org/TR/cssom/#serializing-css-values

Depends on D221988

Differential Revision: https://phabricator.services.mozilla.com/D221989

testing/web-platform/meta/css/css-anchor-position/parsing/position-try-fallbacks-computed.html.ini

@@ -1,3 +0,0 @@
-[position-try-fallbacks-computed.html]
-  [Property position-try-fallbacks value 'flip-start flip-inline flip-block']
-    expected: FAIL

testing/web-platform/meta/css/css-anchor-position/parsing/position-try-fallbacks-parsing.html.ini

@@ -1,9 +0,0 @@
-[position-try-fallbacks-parsing.html]
-  [e.style['position-try-fallbacks'\] = "flip-start flip-inline, flip-block" should set the property value]
-    expected: FAIL
-
-  [e.style['position-try-fallbacks'\] = "flip-start flip-inline flip-block" should set the property value]
-    expected: FAIL
-
-  [e.style['position-try-fallbacks'\] = "--bar flip-inline flip-block" should set the property value]
-    expected: FAIL

testing/web-platform/meta/css/css-anchor-position/parsing/position-try-parsing.html.ini

@@ -1,6 +0,0 @@
-[position-try-parsing.html]
-  [e.style['position-try'\] = "most-block-size flip-inline flip-block, --bar, --baz" should set the property value]
-    expected: FAIL
-
-  [e.style['position-try'\] = "most-inline-size flip-inline flip-block, --foo, --bar" should set position-try-fallbacks]
-    expected: FAIL

testing/web-platform/tests/css/css-anchor-position/parsing/position-try-fallbacks-computed.html

@@ -16,7 +16,7 @@
   test_computed_value("position-try-fallbacks", "flip-start");
   test_computed_value("position-try-fallbacks", "flip-block, flip-inline");
   test_computed_value("position-try-fallbacks", "--foo, --bar");
-  test_computed_value("position-try-fallbacks", "flip-start flip-inline flip-block");
+  test_computed_value("position-try-fallbacks", "flip-start flip-inline flip-block", "flip-block flip-inline flip-start");
   test_computed_value("position-try-fallbacks", "flip-start --flop", "--flop flip-start");
   test_computed_value("position-try-fallbacks", "--flop flip-start");
   test_computed_value("position-try-fallbacks", "left top");

testing/web-platform/tests/css/css-anchor-position/parsing/position-try-fallbacks-parsing.html

@@ -15,14 +15,14 @@
   test_valid_value("position-try-fallbacks", "flip-block");
   test_valid_value("position-try-fallbacks", "flip-block ", 'flip-block');
   test_valid_value("position-try-fallbacks", "flip-start, flip-block");
-  test_valid_value("position-try-fallbacks", "flip-start flip-inline, flip-block");
+  test_valid_value("position-try-fallbacks", "flip-start flip-inline, flip-block", "flip-inline flip-start, flip-block");
   test_valid_value("position-try-fallbacks", "flip-start, flip-start");
-  test_valid_value("position-try-fallbacks", "flip-start flip-inline flip-block");
+  test_valid_value("position-try-fallbacks", "flip-start flip-inline flip-block", "flip-block flip-inline flip-start");
   test_valid_value("position-try-fallbacks", "flip-block, --foo");
   test_valid_value("position-try-fallbacks", "--bar, flip-block flip-start");
   test_valid_value("position-try-fallbacks", "--foo, --bar, --baz");
   test_valid_value("position-try-fallbacks", "--bar flip-block");
-  test_valid_value("position-try-fallbacks", "--bar flip-inline flip-block");
+  test_valid_value("position-try-fallbacks", "--bar flip-inline flip-block", "--bar flip-block flip-inline");
   test_valid_value("position-try-fallbacks", "flip-inline --foo", "--foo flip-inline");
   test_valid_value("position-try-fallbacks", "flip-inline flip-start --foo", "--foo flip-inline flip-start");
   test_valid_value("position-try-fallbacks", "left top");

testing/web-platform/tests/css/css-anchor-position/parsing/position-try-parsing.html

@@ -11,7 +11,7 @@
   test_valid_value("position-try", "most-height none");
   test_valid_value("position-try", "--bar, --baz");
   test_valid_value("position-try", "most-inline-size --baz, flip-inline");
-  test_valid_value("position-try", "most-block-size flip-inline flip-block, --bar, --baz");
+  test_valid_value("position-try", "most-block-size flip-block flip-inline, --bar, --baz");
   test_valid_value("position-try", "normal none", "none");
   test_valid_value("position-try", "most-width none");
   test_valid_value("position-try", "normal --foo", "--foo");
@@ -39,6 +39,6 @@
   });
   test_shorthand_value("position-try", "most-inline-size flip-inline flip-block, --foo, --bar", {
     "position-try-order": "most-inline-size",
-    "position-try-fallbacks": "flip-inline flip-block, --foo, --bar",
+    "position-try-fallbacks": "flip-block flip-inline, --foo, --bar",
   });
 </script>