Auto merge of #16686 - aethanyc:bug1321754, r=heycam

stylo: Parse eSafeAgentSheetFeatures as agent sheet

This was reviewed in https://bugzilla.mozilla.org/show_bug.cgi?id=1321754

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2 files changed, 20 insertions, 0 deletions

diff --git a/components/style/gecko_bindings/structs_debug.rs b/components/style/gecko_bindings/structs_debug.rs
index 07ef42a67ea..cdb6a538892 100644
--- a/components/style/gecko_bindings/structs_debug.rs
+++ b/components/style/gecko_bindings/structs_debug.rs
@@ -5293,18 +5293,28 @@ pub mod root {
  * exposure on the public Web, but are very useful for expressing
  * user style overrides, such as @-moz-document rules.
  *
+ * XXX: eUserSheetFeatures was added in bug 1035091, but some patches in
+ * that bug never landed to use this enum value. Currently, all the features
+ * in user sheet are also available in author sheet.
+ *
  * Agent sheets have access to all author- and user-sheet features
  * plus more extensions that are necessary for internal use but,
  * again, not yet suitable for exposure on the public Web.  Some of
  * these are outright unsafe to expose; in particular, incorrect
  * styling of anonymous box pseudo-elements can violate layout
  * invariants.
+ *
+ * Agent sheets that do not use any unsafe rules could use
+ * eSafeAgentSheetFeatures when creating the sheet. This enum value allows
+ * Servo backend to recognize the sheets as the agent level, but Gecko
+ * backend will parse it under _author_ level.
  */
             #[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)]
             pub enum SheetParsingMode {
                 eAuthorSheetFeatures = 0,
                 eUserSheetFeatures = 1,
                 eAgentSheetFeatures = 2,
+                eSafeAgentSheetFeatures = 3,
             }
             #[repr(C)]
             #[derive(Debug, Copy, Clone)]
diff --git a/components/style/gecko_bindings/structs_release.rs b/components/style/gecko_bindings/structs_release.rs
index 67c2e89d583..f4f43100bc4 100644
--- a/components/style/gecko_bindings/structs_release.rs
+++ b/components/style/gecko_bindings/structs_release.rs
@@ -5222,18 +5222,28 @@ pub mod root {
  * exposure on the public Web, but are very useful for expressing
  * user style overrides, such as @-moz-document rules.
  *
+ * XXX: eUserSheetFeatures was added in bug 1035091, but some patches in
+ * that bug never landed to use this enum value. Currently, all the features
+ * in user sheet are also available in author sheet.
+ *
  * Agent sheets have access to all author- and user-sheet features
  * plus more extensions that are necessary for internal use but,
  * again, not yet suitable for exposure on the public Web.  Some of
  * these are outright unsafe to expose; in particular, incorrect
  * styling of anonymous box pseudo-elements can violate layout
  * invariants.
+ *
+ * Agent sheets that do not use any unsafe rules could use
+ * eSafeAgentSheetFeatures when creating the sheet. This enum value allows
+ * Servo backend to recognize the sheets as the agent level, but Gecko
+ * backend will parse it under _author_ level.
  */
             #[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)]
             pub enum SheetParsingMode {
                 eAuthorSheetFeatures = 0,
                 eUserSheetFeatures = 1,
                 eAgentSheetFeatures = 2,
+                eSafeAgentSheetFeatures = 3,
             }
             #[repr(C)]
             #[derive(Debug, Copy, Clone)]