Remove queryUsageAndQuota API

tools/dom/templates/html/impl/impl_StorageInfo.darttemplate

-// Copyright (c) 2013, 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.
-
-part of $LIBRARYNAME;
-
-$(ANNOTATIONS)$(CLASS_MODIFIERS)class $CLASSNAME$EXTENDS$IMPLEMENTS$NATIVESPEC {
-$!MEMBERS
-  Future<StorageInfoUsage> queryUsageAndQuota(int storageType) {
-    var completer = new Completer<StorageInfoUsage>();
-    _queryUsageAndQuota(storageType,
-        (currentUsageInBytes, currentQuotaInBytes) {
-          completer.complete(new StorageInfoUsage(currentUsageInBytes,
-              currentQuotaInBytes));
-        },
-        (error) { completer.completeError(error); });
-    return completer.future;
-  }
-}
-
-/**
- * A simple container class for the two values that are returned from the
- * futures in requestQuota and queryUsageAndQuota.
- */
-class StorageInfoUsage {
-  final int currentUsageInBytes;
-  final int currentQuotaInBytes;
-  const StorageInfoUsage(this.currentUsageInBytes, this.currentQuotaInBytes);
-}