Roll to pickup pool changes

packages/matcher/lib/src/interfaces.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.
 
 // To decouple the reporting of errors, and allow for extensibility of
 // matchers, we make use of some interfaces.
 
 /// Matchers build up their error messages by appending to
 /// Description objects. This interface is implemented by
 /// StringDescription. This interface is unlikely to need
@@ skipping 10 matching lines @@
 
   /// This is used to add a meaningful description of a value.
   Description addDescriptionOf(value);
 
   /// This is used to add a description of an [Iterable] [list],
   /// with appropriate [start] and [end] markers and inter-element [separator].
   Description addAll(String start, String separator, String end, Iterable list);
 }
 
 /// [expect] Matchers must implement/extend the Matcher class.
+///
 /// The base Matcher class has a generic implementation of [describeMismatch]
 /// so this does not need to be provided unless a more clear description is
 /// required. The other two methods ([matches] and [describe])
 /// must always be provided as they are highly matcher-specific.
 abstract class Matcher {
   const Matcher();
 
   /// This does the matching of the actual vs expected values.
   /// [item] is the actual value. [matchState] can be supplied
   /// and may be used to add details about the mismatch that are too
   /// costly to determine in [describeMismatch].
   bool matches(item, Map matchState);
 
   /// This builds a textual description of the matcher.
   Description describe(Description description);
 
   /// This builds a textual description of a specific mismatch. [item]
   /// is the value that was tested by [matches]; [matchState] is
   /// the [Map] that was passed to and supplemented by [matches]
   /// with additional information about the mismatch, and [mismatchDescription]
-  /// is the [Description] that is being built to decribe the mismatch.
+  /// is the [Description] that is being built to describe the mismatch.
   /// A few matchers make use of the [verbose] flag to provide detailed
   /// information that is not typically included but can be of help in
   /// diagnosing failures, such as stack traces.
   Description describeMismatch(item, Description mismatchDescription,
           Map matchState, bool verbose) =>
       mismatchDescription;
 }