Remove insertRange.

runtime/lib/growable_array.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.
 
 class _GrowableObjectArray<T> implements List<T> {
   factory _GrowableObjectArray._uninstantiable() {
     throw new UnsupportedError(
         "GrowableObjectArray can only be allocated by the VM");
   }
 
@@ skipping 61 matching lines @@
   void removeRange(int start, int end) {
     Arrays.indicesCheck(this, start, end);
     Arrays.copy(this,
                 end,
                 this,
                 start,
                 this.length - end);
     this.length = this.length - (end - start);
   }
 
-  void insertRange(int start, int length, [T initialValue = null]) {
-    if (length == 0) {
-      return;
-    }
-    if ((length < 0) || (length is! int)) {
-      throw new ArgumentError("invalid length specified $length");
-    }
-    if (start < 0 || start > this.length) {
-      throw new RangeError.value(start);
-    }
-    var old_length = this.length;
-    this.length = old_length + length;  // Will expand if needed.
-    Arrays.copy(this,
-                start,
-                this,
-                start + length,
-                old_length - start);
-    for (int i = start; i < start + length; i++) {
-      this[i] = initialValue;
-    }
-  }
-
   List<T> sublist(int start, [int end]) {
     Arrays.indicesCheck(this, start, end);
     if (end == null) end = length;
     int length = end - start;
     if (start == end) return <T>[];
     List list = new _GrowableObjectArray<T>.withCapacity(length);
     list.length = length;
     Arrays.copy(this, start, list, 0, length);
     return list;
   }
@@ skipping 220 matching lines @@
   }
 
   Set<T> toSet() {
     return new Set<T>.from(this);
   }
 
   Map<int, T> asMap() {
     return IterableMixinWorkaround.asMapList(this);
   }
 }