Use pub_semver package in pub.

sdk/lib/_internal/pub/lib/src/solver/solve_report.dart

 // Copyright (c) 2013, 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 pub.solver.solve_report;
 
+import 'package:pub_semver/pub_semver.dart';
+
 import '../lock_file.dart';
 import '../log.dart' as log;
 import '../package.dart';
 import '../source_registry.dart';
 import '../utils.dart';
-import '../version.dart';
 import 'version_solver.dart';
 
 /// Unlike [SolveResult], which is the static data describing a resolution,
 /// this class contains the mutable state used while generating the report
 /// itself.
 ///
 /// It's a report builder.
 class SolveReport {
   final SolveType _type;
   final SourceRegistry _sources;
@@ skipping 216 matching lines @@
   void _writeId(PackageId id) {
     _output.write(id.version);
 
     var source = _sources[id.source];
     if (source != _sources.defaultSource) {
       var description = source.formatDescription(_root.dir, id.description);
       _output.write(" from ${id.source} $description");
     }
   }
 }