Revert "Rename mappedBy to map."

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 'io.dart';
 import 'lock_file.dart';
 import 'log.dart' as log;
@@ skipping 112 matching lines @@
         versionSolver.useLatestVersion(dependency);
       }
       return versionSolver.solve();
     }).then(_installDependencies);
   }
 
   /// Removes the old packages directory, installs all dependencies listed in
   /// [packageVersions], and writes a [LockFile].
   Future _installDependencies(List<PackageId> packageVersions) {
     return cleanDir(path).then((_) {
-      return Future.wait(packageVersions.map((id) {
+      return Future.wait(packageVersions.mappedBy((id) {
         if (id.isRoot) return new Future.immediate(id);
         return install(id);
       }));
     }).then(_saveLockFile)
       .then(_installSelfReference)
       .then(_linkSecondaryPackageDirs);
   }
 
   /// Loads the list of concrete package versions from the `pubspec.lock`, if it
   /// exists. If it doesn't, this completes to an empty [LockFile].
@@ skipping 56 matching lines @@
   }
 
   /// Creates a symlink to the `packages` directory in [dir] and all its
   /// subdirectories.
   Future _linkSecondaryPackageDirsRecursively(String dir) {
     return dirExists(dir).then((exists) {
       if (!exists) return;
       return _linkSecondaryPackageDir(dir)
         .then((_) => _listDirWithoutPackages(dir))
         .then((files) {
-        return Future.wait(files.map((file) {
+        return Future.wait(files.mappedBy((file) {
           return dirExists(file).then((isDir) {
             if (!isDir) return;
             return _linkSecondaryPackageDir(file);
           });
         }));
       });
     });
   }
 
   // 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) {
+      return Future.wait(files.mappedBy((file) {
         if (basename(file) == 'packages') return new Future.immediate([]);
         return dirExists(file).then((isDir) {
           if (!isDir) return [];
           return _listDirWithoutPackages(file);
         }).then((subfiles) {
           var fileAndSubfiles = [file];
           fileAndSubfiles.addAll(subfiles);
           return fileAndSubfiles;
         });
       }));
     }).then(flatten);
   }
 
   /// Creates a symlink to the `packages` directory in [dir] if none exists.
   Future _linkSecondaryPackageDir(String dir) {
     var to = join(dir, 'packages');
     return exists(to).then((exists) {
       if (exists) return;
       return createSymlink(path, to);
     });
   }
 }