Patch a few small autolayout bugs - not a huge fan of the clone() in constraints but fine for now

appkit/src/layout/horizontal.rs

@@ -27,7 +27,7 @@ impl LayoutAnchorX {
     pub fn constraint_equal_to(&self, anchor_to: &LayoutAnchorX) -> LayoutConstraint {
         match (&self.0, &anchor_to.0) {
             (Some(from), Some(to)) => LayoutConstraint::new(unsafe {
-                msg_send![*from, constraintEqualToAnchor:&*to]
+                msg_send![*from, constraintEqualToAnchor:&*to.clone()]
             }),
 
             _ => { panic!("Attempted to create horizontal constraints with an uninitialized anchor!"); }

appkit/src/layout/vertical.rs

@@ -27,7 +27,8 @@ impl LayoutAnchorY {
     pub fn constraint_equal_to(&self, anchor_to: &LayoutAnchorY) -> LayoutConstraint {
         match (&self.0, &anchor_to.0) {
             (Some(from), Some(to)) => LayoutConstraint::new(unsafe {
-                msg_send![*from, constraintEqualToAnchor:&*to]
+                let b: id = msg_send![*from, constraintEqualToAnchor:&*to.clone()];
+                b
             }),
 
             _ => { panic!("Attempted to create vertical constraints with an uninitialized anchor!"); }

appkit/src/view/view.rs

@@ -162,6 +162,22 @@ impl<T> View<T> where T: ViewController + 'static {
         self.objc_controller.register_for_dragged_types(types);
     }
 
+    pub fn top(&self) -> &LayoutAnchorY {
+        &self.objc_controller.top
+    }
+
+    pub fn leading(&self) -> &LayoutAnchorX {
+        &self.objc_controller.leading
+    }
+
+    pub fn trailing(&self) -> &LayoutAnchorX {
+        &self.objc_controller.trailing
+    }
+
+    pub fn bottom(&self) -> &LayoutAnchorY {
+        &self.objc_controller.bottom
+    }
+
     pub fn width(&self) -> &LayoutAnchorDimension {
         &self.objc_controller.width
     }