Auto merge of #15518 - emilio:color, r=SimonSapin

style: Unbox a bunch of color properties.

This builds on https://github.com/servo/rust-cssparser/pull/118.

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ports/geckolib/Cargo.toml

@@ -15,7 +15,7 @@ bindgen = ["style/use_bindgen"]
 [dependencies]
 app_units = "0.3"
 atomic_refcell = "0.1"
-cssparser = {version = "0.7"}
+cssparser = {version = "0.8"}
 env_logger = {version = "0.4", default-features = false} # disable `regex` to reduce code size
 euclid = "0.10.1"
 lazy_static = "0.2"

ports/geckolib/glue.rs

@@ -983,12 +983,12 @@ pub extern "C" fn Servo_DeclarationBlock_AddPresValue(declarations: RawServoDecl
         }
         LonghandId::Color => {
             if let Some(color) = css_value.color_value() {
-                PropertyDeclaration::Color(DeclaredValue::Value(Box::new(
+                PropertyDeclaration::Color(DeclaredValue::Value(
                     specified::CSSRGBA {
                         parsed: convert_nscolor_to_rgba(color),
                         authored: None
                     }
-                )))
+                ))
             } else {
                 error!("stylo: got unexpected non-integer value for color presentation attribute");
                 return