Remove legacy restart code

runtime/observatory/lib/src/elements/debugger.dart

 // Copyright (c) 2014, 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 debugger_page_element;
 
 import 'dart:async';
 import 'dart:svg';
 import 'dart:html';
 import 'dart:math';
@@ skipping 1224 matching lines @@
     await debugger.vm.setName(args[0]);
   }
 
   String helpShort = 'Rename the current Dart virtual machine';
 
   String helpLong = 'Rename the current Dart virtual machine.\n'
       '\n'
       'Syntax: vm name <name>\n';
 }
 
-class VmRestartCommand extends DebuggerCommand {
-  VmRestartCommand(Debugger debugger) : super(debugger, 'restart', []);
-
-  Future handleModalInput(String line) async {
-    if (line == 'yes') {
-      debugger.console.printRed('Restarting VM...');
-      await debugger.vm.restart();
-      debugger.input.exitMode();
-    } else if (line == 'no') {
-      debugger.console.printRed('VM restart canceled.');
-      debugger.input.exitMode();
-    } else {
-      debugger.console.printRed("Please type 'yes' or 'no'");
-    }
-  }
-
-  Future run(List<String> args) async {
-    debugger.input.enterMode('Restart vm? (yes/no)', handleModalInput);
-  }
-
-  String helpShort = 'Restart a Dart virtual machine';
-
-  String helpLong = 'Restart a Dart virtual machine.\n'
-      '\n'
-      'Syntax: vm restart\n';
-}
 
 class VmCommand extends DebuggerCommand {
   VmCommand(Debugger debugger)
       : super(debugger, 'vm', [
           new VmListCommand(debugger),
           new VmNameCommand(debugger),
-          new VmRestartCommand(debugger),
         ]);
 
   Future run(List<String> args) async {
     debugger.console.print("'vm' expects a subcommand (see 'help vm')");
   }
 
   String helpShort = 'Manage a Dart virtual machine';
 
   String helpLong = 'Manage a Dart virtual machine.\n'
       '\n'
@@ skipping 2074 matching lines @@
   ..setAttribute('height', '24')
   ..children = [
     new PathElement()
       ..setAttribute(
           'd',
           'M11 17h2v-6h-2v6zm1-15C6.48 2 2 6.48 2 12s4.48 10 '
           '10 10 10-4.48 10-10S17.52 2 12 2zm0 18c-4.41 '
           '0-8-3.59-8-8s3.59-8 8-8 8 3.59 8 8-3.59 8-8 8zM11 '
           '9h2V7h-2v2z')
   ];