Rationalize Dart mojo and sky package structure

mojo/public/tools/BUILD.gn

 # Copyright 2014 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import("//build/module_args/mojo.gni")
 import("../mojo.gni")
 
 if (mojo_use_prebuilt_mojo_shell) {
   copy("copy_mojo_shell") {
     filename = "mojo_shell"
@@ skipping 68 matching lines @@
       }
     }
     outputs = [
       "$root_out_dir/$filename",
     ]
   }
 }
 
 # This rule can be seen as a sort of adapter. This takes a dart framework
 # loaded from Google Storage and then puts it in a rule which the
-# "dart_package" template in mojo/public/dart/rules.gni can introspect on,
+# "dartzip_package" template in mojo/public/dart/rules.gni can introspect on,
 # accessing the 'label' and 'target_out_dir' variables.
 if (mojo_use_dart_apptest_framework) {
   copy("dart_apptest_framework") {
     sources = [
       "prebuilt/frameworks/apptest.dartzip",
     ]
     outputs = [
       "$target_out_dir/dart_apptest_framework.dartzip",
     ]
   }
 }