Fix some bad documentation links.

sdk/lib/core/errors.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 dart.core;
 
 /**
  * Error objects thrown in the case of a program failure.
  *
  * An `Error` object represents a program failure that the programmer
@@ skipping 345 matching lines @@
 }
 
 /**
  * A specialized [RangeError] used when an index is not in the range
  * `0..indexable.length-1`.
  *
  * Also contains the indexable object, its length at the time of the error,
  * and the invalid index itself.
  */
 class IndexError extends ArgumentError implements RangeError {
-  /** The indexable object that [index] was not a valid index into. */
+  /** The indexable object that [invalidValue] was not a valid index into. */
   final indexable;
   /** The length of [indexable] at the time of the error. */
   final int length;
 
   /**
    * Creates a new [IndexError] stating that [invalidValue] is not a valid index
    * into [indexable].
    *
    * The [length] is the length of [indexable] at the time of the error.
    * If `length` is omitted, it defaults to `indexable.length`.
@@ skipping 173 matching lines @@
  * the first time it is read. If evaluating the initializer expression causes
  * another read of the variable, this error is thrown.
  */
 class CyclicInitializationError extends Error {
   final String variableName;
   CyclicInitializationError([this.variableName]);
   String toString() => variableName == null
       ? "Reading static variable during its initialization"
       : "Reading static variable '$variableName' during its initialization";
 }