Bug 1740230 - Allow matches() / querySelector() / etc on chrome docs to access chrome-only selectors. r=boris

Without this some tests fail with the previous patch because code like:

  https://searchfox.org/mozilla-central/rev/267682a8f45221bf0bfe999d4a0239706a43bc56/browser/base/content/browser-gestureSupport.js#651

starts throwing. Unfortunately I had missed that on my try run, because
the error message didn't include that exception (it seemed like an
intermittent browser-chrome failure instead).

We could expose a ChromeOnly API for this, but this seems better. This
fixes it trivially, and also removes the "no url data" situation from
the selector parser, which is nice.

Differential Revision: https://phabricator.services.mozilla.com/D130818

dom/base/nsINode.cpp

@@ -2867,7 +2867,15 @@ const RawServoSelectorList* nsINode::ParseSelectorList(
   RawServoSelectorList* list = cache.GetListOrInsertFrom(aSelectorString, [&] {
     // Note that we want to cache even if null was returned, because we
     // want to cache the "This is not a valid selector" result.
-    return Servo_SelectorList_Parse(&aSelectorString).Consume();
+    //
+    // NOTE(emilio): Off-hand, getting a CallerType here might seem like a
+    // better idea than using IsDocumentURISchemeChrome(), but that would mean
+    // that we'd need to key the selector cache by that.
+    // IsDocumentURISchemeChrome() gives us the same semantics as any inline
+    // style associated to a document, which seems reasonable.
+    return Servo_SelectorList_Parse(&aSelectorString,
+                                    doc->IsDocumentURISchemeChrome())
+        .Consume();
   });
 
   if (!list) {

servo/components/style/selector_parser.rs

@@ -46,7 +46,7 @@ pub struct SelectorParser<'a> {
     pub namespaces: &'a Namespaces,
     /// The extra URL data of the stylesheet, which is used to look up
     /// whether we are parsing a chrome:// URL style sheet.
-    pub url_data: Option<&'a UrlExtraData>,
+    pub url_data: &'a UrlExtraData,
 }
 
 impl<'a> SelectorParser<'a> {
@@ -54,14 +54,15 @@ impl<'a> SelectorParser<'a> {
     /// account namespaces.
     ///
     /// This is used for some DOM APIs like `querySelector`.
-    pub fn parse_author_origin_no_namespace(
-        input: &str,
-    ) -> Result<SelectorList<SelectorImpl>, ParseError> {
+    pub fn parse_author_origin_no_namespace<'i>(
+        input: &'i str,
+        url_data: &UrlExtraData,
+    ) -> Result<SelectorList<SelectorImpl>, ParseError<'i>> {
         let namespaces = Namespaces::default();
         let parser = SelectorParser {
             stylesheet_origin: Origin::Author,
             namespaces: &namespaces,
-            url_data: None,
+            url_data,
         };
         let mut input = ParserInput::new(input);
         SelectorList::parse(&parser, &mut CssParser::new(&mut input))
@@ -75,7 +76,7 @@ impl<'a> SelectorParser<'a> {
     /// Whether we're parsing selectors in a stylesheet that has chrome
     /// privilege.
     pub fn chrome_rules_enabled(&self) -> bool {
-        self.url_data.map_or(false, |d| d.chrome_rules_enabled()) ||
+        self.url_data.chrome_rules_enabled() ||
             self.stylesheet_origin == Origin::User
     }
 }

servo/components/style/stylesheets/rule_parser.rs

@@ -704,7 +704,7 @@ impl<'a, 'b, 'i> QualifiedRuleParser<'i> for NestedRuleParser<'a, 'b> {
         let selector_parser = SelectorParser {
             stylesheet_origin: self.context.stylesheet_origin,
             namespaces: self.namespaces,
-            url_data: Some(self.context.url_data),
+            url_data: self.context.url_data,
         };
         let selectors = SelectorList::parse(&selector_parser, input)?;
         if self.context.error_reporting_enabled() {

servo/components/style/stylesheets/supports_rule.rs

@@ -335,7 +335,7 @@ impl RawSelector {
                 let parser = SelectorParser {
                     namespaces,
                     stylesheet_origin: context.stylesheet_origin,
-                    url_data: Some(context.url_data),
+                    url_data: context.url_data,
                 };
 
                 #[allow(unused_variables)]

servo/ports/geckolib/glue.rs

@@ -2506,7 +2506,7 @@ pub extern "C" fn Servo_StyleRule_SetSelectorText(
         let parser = SelectorParser {
             stylesheet_origin: contents.origin,
             namespaces: &namespaces,
-            url_data: Some(&url_data),
+            url_data: &url_data,
         };
 
         let mut parser_input = ParserInput::new(&value_str);
@@ -6638,11 +6638,18 @@ pub extern "C" fn Servo_HasPendingRestyleAncestor(
 #[no_mangle]
 pub unsafe extern "C" fn Servo_SelectorList_Parse(
     selector_list: &nsACString,
+    is_chrome: bool,
 ) -> OwnedOrNull<RawServoSelectorList> {
     use style::selector_parser::SelectorParser;
 
+    let url_data = UrlExtraData::from_ptr_ref(if is_chrome {
+        &DUMMY_CHROME_URL_DATA
+    } else {
+        &DUMMY_URL_DATA
+    });
+
     let input = selector_list.as_str_unchecked();
-    let selector_list = match SelectorParser::parse_author_origin_no_namespace(&input) {
+    let selector_list = match SelectorParser::parse_author_origin_no_namespace(&input, url_data) {
         Ok(selector_list) => selector_list,
         Err(..) => return OwnedOrNull::null(),
     };