Recommit changing List.skip/take/revert returns Iterable and remove mappedBy.

utils/pub/entrypoint.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.
 
 library entrypoint;
 
 import 'dart:async';
 
 import '../../pkg/path/lib/path.dart' as path;
 
@@ skipping 116 matching lines @@
     }).then(_installDependencies);
   }
 
   /// Removes the old packages directory, installs all dependencies listed in
   /// [packageVersions], and writes a [LockFile].
   Future _installDependencies(List<PackageId> packageVersions) {
     return cleanDir(packagesDir).then((_) {
       return Future.wait(packageVersions.map((id) {
         if (id.isRoot) return new Future.immediate(id);
         return install(id);
-      }));
+      }).toList());
     }).then(_saveLockFile)
       .then(_installSelfReference)
       .then(_linkSecondaryPackageDirs);
   }
 
   /// Traverses the root's package dependency graph and loads each of the
   /// reached packages. This should only be called after the lockfile has been
   /// successfully generated.
   Future<List<Pubspec>> walkDependencies() {
     return defer(() {
@@ skipping 112 matching lines @@
     return defer(() {
       if (!dirExists(dir)) return;
       return _linkSecondaryPackageDir(dir)
           .then((_) => _listDirWithoutPackages(dir))
           .then((files) {
         return Future.wait(files.map((file) {
           return defer(() {
             if (!dirExists(file)) return;
             return _linkSecondaryPackageDir(file);
           });
-        }));
+        }).toList());
       });
     });
   }
 
   // TODO(nweiz): roll this into [listDir] in io.dart once issue 4775 is fixed.
   /// Recursively lists the contents of [dir], excluding hidden `.DS_Store`
   /// files and `package` files.
   Future<List<String>> _listDirWithoutPackages(dir) {
     return listDir(dir).then((files) {
       return Future.wait(files.map((file) {
         if (path.basename(file) == 'packages') return new Future.immediate([]);
         return defer(() {
           if (!dirExists(file)) return [];
           return _listDirWithoutPackages(file);
         }).then((subfiles) {
           var fileAndSubfiles = [file];
           fileAndSubfiles.addAll(subfiles);
           return fileAndSubfiles;
         });
-      }));
+      }).toList());
     }).then(flatten);
   }
 
   /// Creates a symlink to the `packages` directory in [dir] if none exists.
   Future _linkSecondaryPackageDir(String dir) {
     return defer(() {
       var to = path.join(dir, 'packages');
       if (entryExists(to)) return;
       return createSymlink(packagesDir, to);
     });
   }
 }