Fix typo in doc.

sdk/lib/core/iterable.dart

 // Copyright (c) 2011, 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;
 
 /**
  * A collection of values, or "elements", that can be accessed sequentially.
  *
  * The elements of the iterable are accessed by getting an [Iterator]
@@ skipping 416 matching lines @@
   /**
    * Returns an Iterable that skips leading elements while [test] is satisfied.
    *
    * The filtering happens lazily. Every new Iterator of the returned
    * Iterable iterates over all elements of `this`.
    *
    * The returned iterable provides elements by iterating this iterable,
    * but skipping over all initial elements where `test(element)` returns
    * true. If all elements satisfy `test` the resulting iterable is empty,
    * otherwise it iterates the remaining elements in their original order,
-   * starting with the first element for which `test(element)` returns false,
+   * starting with the first element for which `test(element)` returns false.
    */
   Iterable<E> skipWhile(bool test(E value)) {
     return new SkipWhileIterable<E>(this, test);
   }
 
   /**
    * Returns the first element.
    *
    * Throws a [StateError] if `this` is empty.
    * Otherwise returns the first element in the iteration order,
@@ skipping 225 matching lines @@
  */
 abstract class BidirectionalIterator<E> implements Iterator<E> {
   /**
    * Move back to the previous element.
    *
    * Returns true and updates [current] if successful. Returns false
    * and sets [current] to null if there is no previous element.
    */
   bool movePrevious();
 }