Update charted to 0.4.8 and roll

packages/quiver/lib/pattern.dart

 // Copyright 2013 Google Inc. All Rights Reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
 // You may obtain a copy of the License at
 //
 //     http://www.apache.org/licenses/LICENSE-2.0
 //
 // Unless required by applicable law or agreed to in writing, software
 // distributed under the License is distributed on an "AS IS" BASIS,
@@ skipping 32 matching lines @@
     new _MultiPattern(include, exclude: exclude);
 
 class _MultiPattern extends Pattern {
   final Iterable<Pattern> include;
   final Iterable<Pattern> exclude;
 
   _MultiPattern(Iterable<Pattern> this.include,
       {Iterable<Pattern> this.exclude});
 
   Iterable<Match> allMatches(String str, [int start = 0]) {
-    var _allMatches = [];
+    final _allMatches = <Match>[];
     for (var pattern in include) {
       var matches = pattern.allMatches(str, start);
       if (_hasMatch(matches)) {
         if (exclude != null) {
           for (var excludePattern in exclude) {
             if (_hasMatch(excludePattern.allMatches(str, start))) {
               return [];
             }
           }
         }
-        _allMatches.add(matches);
+        _allMatches.addAll(matches);
       }
     }
-    return _allMatches.expand((x) => x);
+    return _allMatches;
   }
 
   Match matchAsPrefix(String str, [int start = 0]) {
-    return allMatches(str).firstWhere((match) => match.start == start,
-        orElse: () => null);
+    return allMatches(str)
+        .firstWhere((match) => match.start == start, orElse: () => null);
   }
 }
 
 /**
  * Returns true if [pattern] has a single match in [str] that matches the whole
  * string, not a substring.
  */
 bool matchesFull(Pattern pattern, String str) {
   var match = pattern.matchAsPrefix(str);
   return match != null && match.end == str.length;
 }
 
 bool _hasMatch(Iterable<Match> matches) => matches.iterator.moveNext();