Remove deprecated Strings class.

pkg/yaml/lib/model.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.
 
 part of yaml;
 
 // This file contains the node classes for the internal representations of YAML
 // documents. These nodes are used for both the serialization tree and the
 // representation graph.
 
@@ skipping 72 matching lines @@
   bool operator ==(other) {
     // Should be super != other; bug 2554
     if (!(super == other) || other is! _SequenceNode) return false;
     if (content.length != other.content.length) return false;
     for (var i = 0; i < content.length; i++) {
       if (content[i] != other.content[i]) return false;
     }
     return true;
   }
 
-  String toString() =>
-      '$tag [${Strings.join(content.map((e) => '$e'), ', ')}]';
+  String toString() => '$tag [${content.map((e) => '$e').join(', ')}]';
 
   int get hashCode => super.hashCode ^ _hashCode(content);
 
   visit(_Visitor v) => v.visitSequence(this);
 }
 
 /// An alias node is a reference to an anchor.
 class _AliasNode extends _Node {
   _AliasNode(String anchor) : super(new _Tag.scalar(_Tag.yaml("str")), anchor);
 
@@ skipping 67 matching lines @@
             return "\\x${zeroPad(c.toRadixString(16).toUpperCase(), 2)}";
           } else if (c >= 0x100 && c < 0x10000) {
             return "\\u${zeroPad(c.toRadixString(16).toUpperCase(), 4)}";
           } else if (c >= 0x10000) {
             return "\\u${zeroPad(c.toRadixString(16).toUpperCase(), 8)}";
           } else {
             return new String.fromCharCodes([c]);
           }
         }
       });
-      return '"${Strings.join(escapedValue, '')}"';
+      return '"${escapedValue.join()}"';
     }
 
     throw new YamlException("unknown scalar value: $value");
   }
 
   String toString() => '$tag "$content"';
 
   /// Left-pads [str] with zeros so that it's at least [length] characters
   /// long.
   String zeroPad(String str, int length) {
     assert(length >= str.length);
     var prefix = [];
     prefix.insertRange(0, length - str.length, '0');
-    return '${Strings.join(prefix, '')}$str';
+    return '${prefix.join()}$str';
   }
 
   int get hashCode => super.hashCode ^ content.hashCode;
 
   visit(_Visitor v) => v.visitScalar(this);
 }
 
 /// A mapping node represents an unordered map of nodes to nodes.
 class _MappingNode extends _Node {
   /// The node map.
@@ skipping 18 matching lines @@
     var strContent = content.keys
         .map((k) => '${k}: ${content[k]}')
         .join(', ');
     return '$tag {$strContent}';
   }
 
   int get hashCode => super.hashCode ^ _hashCode(content);
 
   visit(_Visitor v) => v.visitMapping(this);
 }