Update cassowary dependency to 0.1.7

sky/sdk/lib/rendering/auto_layout.dart

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 import 'box.dart';
 import 'object.dart';
 import 'package:cassowary/cassowary.dart' as al;
 
 /// Hosts the edge parameters and vends useful methods to construct expressions
 /// for constraints. Also sets up and manages implicit constraints and edit
@@ skipping 10 matching lines @@
   List<al.Constraint> _implicitConstraints;
 
   al.Param get leftEdge => _leftEdge;
   al.Param get rightEdge => _rightEdge;
   al.Param get topEdge => _topEdge;
   al.Param get bottomEdge => _bottomEdge;
 
   al.Expression get width => _rightEdge - _leftEdge;
   al.Expression get height => _bottomEdge - _topEdge;
 
-  al.Expression get horizontalCenter => (_leftEdge + _rightEdge) / al.CM(2.0);
-  al.Expression get verticalCenter => (_topEdge + _bottomEdge) / al.CM(2.0);
+  al.Expression get horizontalCenter => (_leftEdge + _rightEdge) / al.cm(2.0);
+  al.Expression get verticalCenter => (_topEdge + _bottomEdge) / al.cm(2.0);
 
   void _setupLayoutParameters(dynamic context) {
     _leftEdge = new al.Param.withContext(context);
     _rightEdge = new al.Param.withContext(context);
     _topEdge = new al.Param.withContext(context);
     _bottomEdge = new al.Param.withContext(context);
   }
 
   void _setupEditVariablesInSolver(al.Solver solver, double priority) {
     solver.addEditVariables([
@@ skipping 54 matching lines @@
         height: _bottomEdge.value - _topEdge.value);
 
     _renderBox.layout(box, parentUsesSize: false);
     position = new Point(_leftEdge.value, _topEdge.value);
   }
 
   @override
   List<al.Constraint> _constructImplicitConstraints() {
     return [
       // The left edge must be positive
-      _leftEdge >= al.CM(0.0),
+      _leftEdge >= al.cm(0.0),
 
       // Width must be positive
       _rightEdge >= _leftEdge,
     ];
   }
 }
 
 class RenderAutoLayout extends RenderBox
     with ContainerRenderObjectMixin<RenderBox, AutoLayoutParentData>,
          RenderBoxContainerDefaultsMixin<RenderBox, AutoLayoutParentData>,
@@ skipping 98 matching lines @@
     // Call super last as this collects parent data
     super.dropChild(child);
   }
 
   @override
   List<al.Constraint> _constructImplicitConstraints() {
     // Only edits are present on layout containers
     return null;
   }
 }