Convert String and List to abstract classes.

lib/compiler/implementation/lib/core_patch.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.
 
 // Patch file for dart:core classes.
 
 // Patch for 'print' function.
 patch void print(var obj) {
   if (obj is String) {
     Primitives.printString(obj);
@@ skipping 57 matching lines @@
 
 patch class double {
   patch static double parse(String string) => Primitives.parseDouble(string);
 }
 
 patch class NoSuchMethodError {
   patch static String _objectToString(Object object) {
     return Primitives.objectToString(object);
   }
 }
+
+
+// Patch for List implementation.
+patch class List<E> {
+  patch factory List([int length]) => Primitives.newList(length);
+}
+
+// Patch for String implementation.
+// TODO(ager): Split out into date_patch.dart and allow #source
+// in patch files?
+patch class String {
+  patch factory String.fromCharCodes(List<int> charCodes) {
+    checkNull(charCodes);
+    if (!isJsArray(charCodes)) {
+      if (charCodes is !List) throw new IllegalArgumentException(charCodes);
+      charCodes = new List.from(charCodes);
+    }
+    return Primitives.stringFromCharCodes(charCodes);
+  }
+}
+
+patch class Strings {
+  patch static String join(List<String> strings, String separator) {
+    checkNull(strings);
+    checkNull(separator);
+    if (separator is !String) throw new IllegalArgumentException(separator);
+    return stringJoinUnchecked(_toJsStringArray(strings), separator);
+  }
+
+  patch static String concatAll(List<String> strings) {
+    return stringJoinUnchecked(_toJsStringArray(strings), "");
+  }
+
+  static List _toJsStringArray(List<String> strings) {
+    checkNull(strings);
+    var array;
+    final length = strings.length;
+    if (isJsArray(strings)) {
+      array = strings;
+      for (int i = 0; i < length; i++) {
+        final string = strings[i];
+        checkNull(string);
+        if (string is !String) throw new IllegalArgumentException(string);
+      }
+    } else {
+      array = new List(length);
+      for (int i = 0; i < length; i++) {
+        final string = strings[i];
+        checkNull(string);
+        if (string is !String) throw new IllegalArgumentException(string);
+        array[i] = string;
+      }
+    }
+    return array;
+  }
+}