Auto merge of #20082 - emilio:ignore-existing-styles, r=bholley

style: Cleanup always-false argument to Servo_ResolveStyleLazily.

I changed this setup in https://bugzilla.mozilla.org/show_bug.cgi?id=1414999,
because it was totally unsound.

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4 files changed, 4 insertions, 11 deletions

diff --git a/components/layout/query.rs b/components/layout/query.rs
index afe5b50d909..bea54d43364 100644
--- a/components/layout/query.rs
+++ b/components/layout/query.rs
@@ -693,7 +693,7 @@ pub fn process_resolved_style_request<'a, N>(context: &LayoutContext,
         thread_local: &mut tlc,
     };
 
-    let styles = resolve_style(&mut context, element, RuleInclusion::All, false, pseudo.as_ref());
+    let styles = resolve_style(&mut context, element, RuleInclusion::All, pseudo.as_ref());
     let style = styles.primary();
     let longhand_id = match *property {
         PropertyId::LonghandAlias(id, _) |
diff --git a/components/style/gecko/generated/bindings.rs b/components/style/gecko/generated/bindings.rs
index 94bcc13fcfc..a801c5a9c5f 100644
--- a/components/style/gecko/generated/bindings.rs
+++ b/components/style/gecko/generated/bindings.rs
@@ -3200,7 +3200,6 @@ extern "C" {
         rule_inclusion: StyleRuleInclusion,
         snapshots: *const ServoElementSnapshotTable,
         set: RawServoStyleSetBorrowed,
-        ignore_existing_styles: bool,
     ) -> ServoStyleContextStrong;
 }
 extern "C" {
diff --git a/components/style/traversal.rs b/components/style/traversal.rs
index 6a99d597d1b..8944752f642 100644
--- a/components/style/traversal.rs
+++ b/components/style/traversal.rs
@@ -300,7 +300,6 @@ pub fn resolve_style<E>(
     context: &mut StyleContext<E>,
     element: E,
     rule_inclusion: RuleInclusion,
-    ignore_existing_style: bool,
     pseudo: Option<&PseudoElement>,
 ) -> ElementStyles
 where
@@ -309,7 +308,6 @@ where
     use style_resolver::StyleResolverForElement;
 
     debug_assert!(rule_inclusion == RuleInclusion::DefaultOnly ||
-                  ignore_existing_style ||
                   pseudo.map_or(false, |p| p.is_before_or_after()) ||
                   element.borrow_data().map_or(true, |d| !d.has_styles()),
                   "Why are we here?");
@@ -321,7 +319,7 @@ where
     let mut style = None;
     let mut ancestor = element.traversal_parent();
     while let Some(current) = ancestor {
-        if rule_inclusion == RuleInclusion::All && !ignore_existing_style {
+        if rule_inclusion == RuleInclusion::All {
             if let Some(data) = current.borrow_data() {
                 if let Some(ancestor_style) = data.styles.get_primary() {
                     style = Some(ancestor_style.clone());
diff --git a/ports/geckolib/glue.rs b/ports/geckolib/glue.rs
index 332193c1817..9f6a64e0dd1 100644
--- a/ports/geckolib/glue.rs
+++ b/ports/geckolib/glue.rs
@@ -3646,7 +3646,6 @@ pub extern "C" fn Servo_ResolveStyleLazily(
     rule_inclusion: StyleRuleInclusion,
     snapshots: *const ServoElementSnapshotTable,
     raw_data: RawServoStyleSetBorrowed,
-    ignore_existing_styles: bool,
 ) -> ServoStyleContextStrong {
     debug_assert!(!snapshots.is_null());
     let global_style_data = &*GLOBAL_STYLE_DATA;
@@ -3678,14 +3677,12 @@ pub extern "C" fn Servo_ResolveStyleLazily(
     let is_before_or_after = pseudo.as_ref().map_or(false, |p| p.is_before_or_after());
 
     // In the common case we already have the style. Check that before setting
-    // up all the computation machinery. (Don't use it when we're getting
-    // default styles or in a bfcached document (as indicated by
-    // ignore_existing_styles), though.)
+    // up all the computation machinery.
     //
     // Also, only probe in the ::before or ::after case, since their styles may
     // not be in the `ElementData`, given they may exist but not be applicable
     // to generate an actual pseudo-element (like, having a `content: none`).
-    if rule_inclusion == RuleInclusion::All && !ignore_existing_styles {
+    if rule_inclusion == RuleInclusion::All {
         let styles = element.mutate_data().and_then(|d| {
             if d.has_styles() {
                 finish(&d.styles, is_before_or_after)
@@ -3714,7 +3711,6 @@ pub extern "C" fn Servo_ResolveStyleLazily(
         &mut context,
         element,
         rule_inclusion,
-        ignore_existing_styles,
         pseudo.as_ref()
     );