Update pub to use the new command runner API in args.

sdk/lib/_internal/pub/lib/src/command/global.dart

Index: sdk/lib/_internal/pub/lib/src/command/global.dart
diff --git a/sdk/lib/_internal/pub/lib/src/command/global.dart b/sdk/lib/_internal/pub/lib/src/command/global.dart
index c1b17302f6fd0a2e627a4c943f2b8b01651d2d78..c2ddfd8e3bdf110836d97aed551931e75cb6b01b 100644
--- a/sdk/lib/_internal/pub/lib/src/command/global.dart
+++ b/sdk/lib/_internal/pub/lib/src/command/global.dart
@@ -12,13 +12,14 @@ import 'global_run.dart';
 
 /// Handles the `global` pub command.
 class GlobalCommand extends PubCommand {
+  String get name => "global";
   String get description => "Work with global packages.";
-  String get usage => "pub global <subcommand>";
+  String get invocation => "pub global <subcommand>";
 
-  final subcommands = {
-    "activate": new GlobalActivateCommand(),
-    "deactivate": new GlobalDeactivateCommand(),
-    "list": new GlobalListCommand(),
-    "run": new GlobalRunCommand()
-  };
+  GlobalCommand() {
+    addSubcommand(new GlobalActivateCommand());
+    addSubcommand(new GlobalDeactivateCommand());
+    addSubcommand(new GlobalListCommand());
+    addSubcommand(new GlobalRunCommand());
+  }
 }