Auto merge of #19374 - heycam:compute-color, r=TYLin

geckolib: Return from Servo_ComputeColor whether the value was currentcolor.

Servo part of https://bugzilla.mozilla.org/show_bug.cgi?id=1420026, reviewed there by TYLin.

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components/style/gecko/generated/bindings.rs

@@ -1574,7 +1574,7 @@ extern "C" {
 } extern "C" {
  pub fn Servo_IsValidCSSColor ( value : * const nsAString , ) -> bool ; 
 } extern "C" {
- pub fn Servo_ComputeColor ( set : RawServoStyleSetBorrowedOrNull , current_color : nscolor , value : * const nsAString , result_color : * mut nscolor , ) -> bool ; 
+ pub fn Servo_ComputeColor ( set : RawServoStyleSetBorrowedOrNull , current_color : nscolor , value : * const nsAString , result_color : * mut nscolor , was_current_color : * mut bool , ) -> bool ; 
 } extern "C" {
  pub fn Servo_ParseIntersectionObserverRootMargin ( value : * const nsAString , result : * mut nsCSSRect , ) -> bool ; 
 } extern "C" {
@@ -1587,4 +1587,4 @@ extern "C" {
  pub fn Gecko_ContentList_AppendAll ( aContentList : * mut nsSimpleContentList , aElements : * mut * const RawGeckoElement , aLength : usize , ) ; 
 } extern "C" {
  pub fn Gecko_GetElementsWithId ( aDocument : * const nsIDocument , aId : * mut nsAtom , ) -> * const nsTArray < * mut Element > ; 
-}
+}

ports/geckolib/glue.rs

@@ -4559,6 +4559,7 @@ pub extern "C" fn Servo_ComputeColor(
     current_color: structs::nscolor,
     value: *const nsAString,
     result_color: *mut structs::nscolor,
+    was_current_color: *mut bool,
 ) -> bool {
     use style::gecko;
 
@@ -4593,6 +4594,11 @@ pub extern "C" fn Servo_ComputeColor(
                 Some(computed_color) => {
                     let rgba = computed_color.to_rgba(current_color);
                     *result_color = gecko::values::convert_rgba_to_nscolor(&rgba);
+                    if !was_current_color.is_null() {
+                        unsafe {
+                            *was_current_color = computed_color.is_currentcolor();
+                        }
+                    }
                     true
                 }
                 None => false,