pkg/csslib: fixed analysis error, more cleanup

pkg/csslib/lib/visitor.dart

 // Copyright (c) 2012, 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.
 
 library csslib.visitor;
 
 import 'package:source_maps/span.dart' show Span;
 import 'parser.dart';
 
 part 'src/css_printer.dart';
@@ skipping 93 matching lines @@
   void visitMarginExpression(MarginExpression node);
   void visitBorderExpression(BorderExpression node);
   void visitHeightExpression(HeightExpression node);
   void visitPaddingExpression(PaddingExpression node);
   void visitWidthExpression(WidthExpression node);
 }
 
 /** Base vistor class for the style sheet AST. */
 class Visitor implements VisitorBase {
   /** Helper function to walk a list of nodes. */
-  void _visitNodeList(list) {
+  void _visitNodeList(List<TreeNode> list) {
     // Don't use iterable otherwise the list can't grow while using Visitor.
     // It certainly can't have items deleted before the index being iterated
     // but items could be added after the index.
     for (var index = 0; index < list.length; index++) {
       list[index].visit(this);
     }
   }
 
   void visitTree(StyleSheet tree) => visitStyleSheet(tree);
 
@@ skipping 62 matching lines @@
   void visitKeyFrameBlock(KeyFrameBlock node) {
     visitExpressions(node._blockSelectors);
     visitDeclarationGroup(node._declarations);
   }
 
   void visitFontFaceDirective(FontFaceDirective node) {
     visitDeclarationGroup(node._declarations);
   }
 
   void visitStyletDirective(StyletDirective node) {
-    _visitNodeList(node._rulesets);
+    _visitNodeList(node.rulesets);
   }
 
   void visitNamespaceDirective(NamespaceDirective node) { }
 
   void visitVarDefinitionDirective(VarDefinitionDirective node) {
     visitVarDefinition(node.def);
   }
 
   void visitMixinRulesetDirective(MixinRulesetDirective node) {
     _visitNodeList(node.rulesets);
@@ skipping 15 matching lines @@
   void visitContentDirective(ContentDirective node) {
     // TODO(terry): TBD
   }
 
   void visitRuleSet(RuleSet node) {
     visitSelectorGroup(node._selectorGroup);
     visitDeclarationGroup(node._declarationGroup);
   }
 
   void visitDeclarationGroup(DeclarationGroup node) {
-    _visitNodeList(node._declarations);
+    _visitNodeList(node.declarations);
   }
 
   void visitMarginGroup(MarginGroup node) => visitDeclarationGroup(node);
 
   void visitDeclaration(Declaration node) {
     visitIdentifier(node._property);
     if (node._expression != null) node._expression.visit(this);
   }
 
   void visitVarDefinition(VarDefinition node) {
@@ skipping 78 matching lines @@
   void visitPseudoClassFunctionSelector(PseudoClassFunctionSelector node) =>
       visitSimpleSelector(node);
 
   void visitPseudoElementFunctionSelector(PseudoElementFunctionSelector node) =>
       visitSimpleSelector(node);
 
   void visitNegationSelector(NegationSelector node) =>
       visitSimpleSelector(node);
 
   void visitSelectorExpression(SelectorExpression node) {
-    _visitNodeList(node._expressions);
+    _visitNodeList(node.expressions);
   }
 
   void visitUnicodeRangeTerm(UnicodeRangeTerm node) { }
 
   void visitLiteralTerm(LiteralTerm node) { }
 
   void visitHexColorTerm(HexColorTerm node) { }
 
   void visitNumberTerm(NumberTerm node) { }
 
@@ skipping 132 matching lines @@
   void visitPaddingExpression(PaddingExpression node) {
     // TODO(terry): TBD
     throw UnimplementedError;
   }
 
   void visitWidthExpression(WidthExpression node) {
     // TODO(terry): TBD
     throw UnimplementedError;
   }
 }