servo: Merge #16739 - Fix serialisation of 'image-orientation: <angle> flip' (from nox:image-orientation); r=SimonSapin

Source-Repo: https://github.com/servo/servo
Source-Revision: 09c8978c5bdd77bdbb16469e502fa53659f56046

--HG--
extra : subtree_source : https%3A//hg.mozilla.org/projects/converted-servo-linear
extra : subtree_revision : 9543c7922b5e8f5a6290dd82a839395fe5b388cb

servo/components/style/properties/longhand/inherited_box.mako.rs

@@ -168,7 +168,7 @@ ${helpers.single_keyword("image-rendering",
                 computed_value::T::AngleWithFlipped(angle, flipped) => {
                     try!(angle.to_css(dest));
                     if flipped {
-                        try!(dest.write_str(" flipped"));
+                        try!(dest.write_str(" flip"));
                     }
                     Ok(())
                 },