servo: Merge #20481 - style: Derive a debug impl instead of implementing by hand (from emilio:debug-wat); r=nox

Source-Repo: https://github.com/servo/servo
Source-Revision: 39018f933997e266e11968d82f556af15c5321d8

--HG--
extra : subtree_source : https%3A//hg.mozilla.org/projects/converted-servo-linear
extra : subtree_revision : 9ca7de120848377507ed4048882b6c6835412fdd

servo/components/style/values/generics/image.rs

@@ -120,7 +120,7 @@ pub enum GradientItem<Color, LengthOrPercentage> {
 
 /// A color stop.
 /// <https://drafts.csswg.org/css-images/#typedef-color-stop-list>
-#[derive(Clone, Copy, MallocSizeOf, PartialEq, ToComputedValue, ToCss)]
+#[derive(Clone, Copy, Debug, MallocSizeOf, PartialEq, ToComputedValue, ToCss)]
 pub struct ColorStop<Color, LengthOrPercentage> {
     /// The color of this stop.
     pub color: Color,
@@ -310,15 +310,3 @@ where
         }
     }
 }
-
-impl<C, L> fmt::Debug for ColorStop<C, L>
-    where C: fmt::Debug, L: fmt::Debug,
-{
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        write!(f, "{:?}", self.color)?;
-        if let Some(ref pos) = self.position {
-            write!(f, " {:?}", pos)?;
-        }
-        Ok(())
-    }
-}