Revert "Rename mappedBy to map."

utils/pub/entrypoint.dart

Index: utils/pub/entrypoint.dart
diff --git a/utils/pub/entrypoint.dart b/utils/pub/entrypoint.dart
index d562997f9aae2890a4404fb63b601072c6e79d05..30bfeb1650a37f6af89274ae9180f255b30578eb 100644
--- a/utils/pub/entrypoint.dart
+++ b/utils/pub/entrypoint.dart
@@ -130,7 +130,7 @@ class Entrypoint {
   /// [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);
       }));
@@ -207,7 +207,7 @@ class Entrypoint {
       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);
@@ -222,7 +222,7 @@ class Entrypoint {
   /// 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 [];