Get rid of all the library tags.

lib/src/location.dart

 // Copyright (c) 2014, 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.
 
-library source_span.location;
-
 import 'span.dart';
 
 // TODO(nweiz): Use SourceLocationMixin once we decide to cut a release with
 // breaking changes. See SourceLocationMixin for details.
 
 /// A class that describes a single location within a source file.
 ///
 /// This class should not be extended. Instead, [SourceLocationBase] should be
 /// extended instead.
 class SourceLocation implements Comparable<SourceLocation> {
@@ skipping 74 matching lines @@
 
   String toString() => '<$runtimeType: $offset $toolString>';
 }
 
 /// A base class for source locations with [offset], [line], and [column] known
 /// at construction time.
 class SourceLocationBase extends SourceLocation {
   SourceLocationBase(int offset, {sourceUrl, int line, int column})
       : super(offset, sourceUrl: sourceUrl, line: line, column: column);
 }