Roll Observatory deps (charted -> ^0.3.0)

packages/csslib/lib/src/polyfill.dart

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 part of csslib.parser;
 
 /**
  * CSS polyfill emits CSS to be understood by older parsers that which do not
  * understand (var, calc, etc.).
  */
 class PolyFill {
   final Messages _messages;
-  final bool _warningsAsErrors;
   Map<String, VarDefinition> _allVarDefinitions =
       new Map<String, VarDefinition>();
 
   Set<StyleSheet> allStyleSheets = new Set<StyleSheet>();
 
   /**
    * [_pseudoElements] list of known pseudo attributes found in HTML, any
    * CSS pseudo-elements 'name::custom-element' is mapped to the manged name
    * associated with the pseudo-element key.
    */
-  PolyFill(this._messages, this._warningsAsErrors);
+  PolyFill(this._messages);
 
   /**
    * Run the analyzer on every file that is a style sheet or any component that
    * has a style tag.
    */
   void process(StyleSheet styleSheet, {List<StyleSheet> includes: null}) {
     if (includes != null) {
       processVarDefinitions(includes);
     }
     processVars(styleSheet);
@@ skipping 185 matching lines @@
     super.visitDeclarationGroup(node);
   }
 }
 
 /** Find terminal definition (non VarUsage implies real CSS value). */
 VarDefinition _findTerminalVarDefinition(
     Map<String, VarDefinition> varDefs, VarDefinition varDef) {
   var expressions = varDef.expression as Expressions;
   for (var expr in expressions.expressions) {
     if (expr is VarUsage) {
-      var usageName = (expr as VarUsage).name;
+      var usageName = expr.name;
       var foundDef = varDefs[usageName];
 
       // If foundDef is unknown check if defaultValues; if it exist then resolve
       // to terminal value.
       if (foundDef == null) {
         // We're either a VarUsage or terminal definition if in varDefs;
         // either way replace VarUsage with it's default value because the
         // VarDefinition isn't found.
-        var defaultValues = (expr as VarUsage).defaultValues;
+        var defaultValues = expr.defaultValues;
         var replaceExprs = expressions.expressions;
         assert(replaceExprs.length == 1);
         replaceExprs.replaceRange(0, 1, defaultValues);
         return varDef;
       }
       if (foundDef is VarDefinition) {
         return _findTerminalVarDefinition(varDefs, foundDef);
       }
     } else {
       // Return real CSS property.
       return varDef;
     }
   }
 
   // Didn't point to a var definition that existed.
   return varDef;
 }