Auto merge of #15983 - canaltinova:pseudo-classes, r=upsuper

Stylo: Add some missing pseudo classes

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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 [Bug 1341739](https://bugzilla.mozilla.org/show_bug.cgi?id=1341739)

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- [X] These changes do not require tests because they are stylo changes.

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components/style/element_state.rs

@@ -37,7 +37,13 @@ bitflags! {
         const IN_TARGET_STATE = 0x100,
         #[doc = "https://fullscreen.spec.whatwg.org/#%3Afullscreen-pseudo-class"]
         const IN_FULLSCREEN_STATE = 0x200,
+        #[doc = "https://html.spec.whatwg.org/multipage/#selector-valid"]
+        const IN_VALID_STATE = 0x400,
+        #[doc = "https://html.spec.whatwg.org/multipage/#selector-invalid"]
+        const IN_INVALID_STATE = 0x800,
+        #[doc = "Non-standard: https://developer.mozilla.org/en-US/docs/Web/CSS/:-moz-ui-valid"]
+        const IN_MOZ_UI_VALID_STATE = 0x1000,
         #[doc = "https://html.spec.whatwg.org/multipage/#selector-read-write"]
-        const IN_READ_WRITE_STATE = 0x400,
+        const IN_READ_WRITE_STATE = 0x2000,
     }
 }

components/style/gecko/non_ts_pseudo_class_list.rs

@@ -44,6 +44,11 @@ macro_rules! apply_non_ts_list {
                 ("disabled", Disabled, disabled, IN_DISABLED_STATE, _),
                 ("checked", Checked, checked, IN_CHECKED_STATE, _),
                 ("indeterminate", Indeterminate, indeterminate, IN_INDETERMINATE_STATE, _),
+                ("placeholder-shown", PlaceholderShown, placeholderShown, IN_PLACEHOLDER_SHOWN_STATE, _),
+                ("target", Target, target, IN_TARGET_STATE, _),
+                ("valid", Valid, valid, IN_VALID_STATE, _),
+                ("invalid", Invalid, invalid, IN_INVALID_STATE, _),
+                ("-moz-ui-valid", MozUIValid, mozUIValid, IN_MOZ_UI_VALID_STATE, _),
                 ("read-write", ReadWrite, _, IN_READ_WRITE_STATE, _),
                 ("read-only", ReadOnly, _, IN_READ_WRITE_STATE, _),
 

components/style/gecko/wrapper.rs

@@ -651,7 +651,12 @@ impl<'le> ::selectors::Element for GeckoElement<'le> {
             NonTSPseudoClass::Checked |
             NonTSPseudoClass::ReadWrite |
             NonTSPseudoClass::Fullscreen |
-            NonTSPseudoClass::Indeterminate => {
+            NonTSPseudoClass::Indeterminate |
+            NonTSPseudoClass::PlaceholderShown |
+            NonTSPseudoClass::Target |
+            NonTSPseudoClass::Valid |
+            NonTSPseudoClass::Invalid |
+            NonTSPseudoClass::MozUIValid => {
                 self.get_state().contains(pseudo_class.state_flag())
             },
             NonTSPseudoClass::ReadOnly => {