Auto merge of #16610 - Manishearth:fixup-overflow, r=emilio

overflow: -moz-scrollbars-none is shorthand-only

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components/style/properties/longhand/box.mako.rs

@@ -407,7 +407,6 @@ ${helpers.single_keyword("overflow-clip-box", "padding-box content-box",
 // FIXME(pcwalton, #2742): Implement scrolling for `scroll` and `auto`.
 ${helpers.single_keyword("overflow-x", "visible hidden scroll auto",
                          need_clone=True, animation_value_type="none",
-                         extra_gecko_aliases="-moz-scrollbars-none=hidden",
                          extra_gecko_values="-moz-hidden-unscrollable",
                          custom_consts=overflow_custom_consts,
                          gecko_constant_prefix="NS_STYLE_OVERFLOW",

components/style/properties/shorthand/box.mako.rs

@@ -27,6 +27,12 @@
                         overflow_y: SpecifiedValue::scroll,
                     })
                 }
+                "-moz-scrollbars-none" => {
+                    Ok(Longhands {
+                        overflow_x: SpecifiedValue::hidden,
+                        overflow_y: SpecifiedValue::hidden,
+                    })
+                }
                 _ => Err(())
             });
             if moz_kw_found.is_ok() {