Auto merge of #25627 - pshaughn:definedpseudo, r=emilio,jdm

Implement :defined CSS selector

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ElementState::IN_DEFINED_STATE already existed but wasn't hooked up to anything; now it is set appropriately, and CSS is aware of it. The main test for this selector needed the window named getter for no important reason, so I made a one-line test change to avoid that. Remaining failures in the test are all about SVG elements.

---
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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #25010

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- [X] There are tests for these changes OR
- [ ] These changes do not require tests because ___

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1 files changed, 4 insertions, 0 deletions

diff --git a/components/style/servo/selector_parser.rs b/components/style/servo/selector_parser.rs
index 942dcdba1bb..599b603f4ff 100644
--- a/components/style/servo/selector_parser.rs
+++ b/components/style/servo/selector_parser.rs
@@ -278,6 +278,7 @@ pub enum NonTSPseudoClass {
     Active,
     AnyLink,
     Checked,
+    Defined,
     Disabled,
     Enabled,
     Focus,
@@ -332,6 +333,7 @@ impl ToCss for NonTSPseudoClass {
             Active => ":active",
             AnyLink => ":any-link",
             Checked => ":checked",
+            Defined => ":defined",
             Disabled => ":disabled",
             Enabled => ":enabled",
             Focus => ":focus",
@@ -371,6 +373,7 @@ impl NonTSPseudoClass {
             Focus => ElementState::IN_FOCUS_STATE,
             Fullscreen => ElementState::IN_FULLSCREEN_STATE,
             Hover => ElementState::IN_HOVER_STATE,
+            Defined => ElementState::IN_DEFINED_STATE,
             Enabled => ElementState::IN_ENABLED_STATE,
             Disabled => ElementState::IN_DISABLED_STATE,
             Checked => ElementState::IN_CHECKED_STATE,
@@ -436,6 +439,7 @@ impl<'a, 'i> ::selectors::Parser<'i> for SelectorParser<'a> {
             "active" => Active,
             "any-link" => AnyLink,
             "checked" => Checked,
+            "defined" => Defined,
             "disabled" => Disabled,
             "enabled" => Enabled,
             "focus" => Focus,