Auto merge of #8533 - Ms2ger:legacy, r=nox

Remove the `legacy` module.

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components/layout/table_cell.rs

@@ -20,7 +20,6 @@ use model::MaybeAuto;
 use std::fmt;
 use std::sync::Arc;
 use style::computed_values::{border_collapse, border_top_style};
-use style::legacy::UnsignedIntegerAttribute;
 use style::properties::ComputedValues;
 use table::InternalTable;
 use table_row::{CollapsedBorder, CollapsedBorderProvenance};
@@ -52,8 +51,7 @@ impl TableCellFlow {
         TableCellFlow {
             block_flow: BlockFlow::from_fragment(fragment, None),
             collapsed_borders: CollapsedBordersForCell::new(),
-            column_span: node.get_unsigned_integer_attribute(UnsignedIntegerAttribute::ColSpan)
-                             .unwrap_or(1),
+            column_span: node.get_colspan(),
             visible: visible,
         }
     }

components/layout/wrapper.rs

@@ -64,7 +64,6 @@ use std::sync::Arc;
 use string_cache::{Atom, Namespace};
 use style::computed_values::content::ContentItem;
 use style::computed_values::{content, display, white_space};
-use style::legacy::UnsignedIntegerAttribute;
 use style::node::TElementAttributes;
 use style::properties::ComputedValues;
 use style::properties::{PropertyDeclaration, PropertyDeclarationBlock};
@@ -643,12 +642,6 @@ impl<'le> TElementAttributes for LayoutElement<'le> {
         }
     }
 
-    fn get_unsigned_integer_attribute(&self, attribute: UnsignedIntegerAttribute) -> Option<u32> {
-        unsafe {
-            self.element.get_unsigned_integer_attribute_for_layout(attribute)
-        }
-    }
-
     #[inline]
     fn get_attr<'a>(&'a self, namespace: &Namespace, name: &Atom) -> Option<&'a str> {
         unsafe {
@@ -885,18 +878,6 @@ impl<'ln> ThreadSafeLayoutNode<'ln> {
         }
     }
 
-    pub fn get_unsigned_integer_attribute(self, attribute: UnsignedIntegerAttribute)
-                                          -> Option<u32> {
-        unsafe {
-            match self.get_jsmanaged().downcast::<Element>() {
-                Some(element) => {
-                    element.get_unsigned_integer_attribute_for_layout(attribute)
-                }
-                None => panic!("not an element!")
-            }
-        }
-    }
-
     /// Get the description of how to account for recent style changes.
     /// This is a simple bitfield and fine to copy by value.
     pub fn restyle_damage(self) -> RestyleDamage {
@@ -1039,6 +1020,12 @@ impl<'ln> ThreadSafeLayoutNode<'ln> {
             iframe_element.pipeline_id().unwrap()
         }
     }
+
+    pub fn get_colspan(&self) -> u32 {
+        unsafe {
+            self.get_jsmanaged().downcast::<Element>().unwrap().get_colspan()
+        }
+    }
 }
 
 pub struct ThreadSafeLayoutNodeChildrenIterator<'a> {