Remove Futures class, move methods to Future.

utils/pub/version_solver.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.
 
 /// Attempts to resolve a set of version constraints for a package dependency
 /// graph and select an appropriate set of best specific versions for all
 /// dependent packages. It works iteratively and tries to reach a stable
 /// solution where the constraints of all dependencies are met. If it fails to
 /// reach a solution after a certain number of iterations, it assumes the
 /// dependency graph is unstable and reports and error.
@@ skipping 236 matching lines @@
 
   Future process(VersionSolver solver) {
     log.fine("Changing $package to version $version.");
 
     var dependency = solver.getDependency(package);
     var oldVersion = dependency.version;
     solver.setVersion(package, version);
 
     // The dependencies between the old and new version may be different. Walk
     // them both and update any constraints that differ between the two.
-    return Futures.wait([
+    return Future.wait([
         getDependencyRefs(solver, oldVersion),
         getDependencyRefs(solver, version)]).then((list) {
       var oldDependencyRefs = list[0];
       var newDependencyRefs = list[1];
 
       for (var oldRef in oldDependencyRefs.values) {
         if (newDependencyRefs.containsKey(oldRef.name)) {
           // The dependency is in both versions of this package, but its
           // constraint may have changed.
           var newRef = newDependencyRefs.remove(oldRef.name);
@@ skipping 432 matching lines @@
 
   String toString() {
     // TODO(nweiz): Dump descriptions to YAML when that's supported.
     return "Incompatible dependencies on '$package':\n"
         "- '$depender1' depends on it with description "
         "${json.stringify(description1)}\n"
         "- '$depender2' depends on it with description "
         "${json.stringify(description2)}";
   }
 }