Issue 471: Support WP8.1

Src/GoogleApis.Auth.WP81/OAuth2/AuthorizationCodeWPInstalledApp.cs

Index: Src/GoogleApis.Auth.WP81/OAuth2/AuthorizationCodeWPInstalledApp.cs
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 b/Src/GoogleApis.Auth.WP81/OAuth2/AuthorizationCodeWPInstalledApp.cs
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 /*
 Copyright 2014 Google Inc
 Licensed under the Apache License, Version 2.0 (the "License");
 you may not use this file except in compliance with the License.
 You may obtain a copy of the License at
 http://www.apache.org/licenses/LICENSE-2.0
 Unless required by applicable law or agreed to in writing, software
 distributed under the License is distributed on an "AS IS" BASIS,
 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 See the License for the specific language governing permissions and
 limitations under the License.
 */
 using System;
 using System.Threading;
 using System.Threading.Tasks;
 using Google.Apis.Auth.OAuth2.Flows;
 namespace Google.Apis.Auth.OAuth2
 {
 /// <summary>
 /// OAuth 2.0 authorization code flow for a Windows Phone 8.1 installed application that persists end-user
 /// credentials.
 /// <remarks>
 /// This installed app class uses an internal <see cref="AuthorizationCodeInstalledApp"/> with a
 /// <see cref="Google.Apis.Auth.OAuth2.AuthorizationCodeBroker"/> for retrieving the authorization code.
 /// </remarks>
 /// </summary>
 public sealed class AuthorizationCodeWPInstalledApp : IAuthorizationCodeInstalledApp
 {
 private readonly IAuthorizationCodeInstalledApp innerInstallApp;
 /// <summary>
 /// Constructs a new authorization code for Windows Store application targeting an installed application flow.
 /// </summary>
 /// <param name="authorizationCodeFlowInitializer">An authorization code flow initializer.</param>
 public AuthorizationCodeWPInstalledApp(AuthorizationCodeFlow.Initializer authorizationCodeFlowInitializer)
 {
 innerInstallApp = new AuthorizationCodeInstalledApp(
 new AuthorizationCodeFlow(authorizationCodeFlowInitializer), new AuthorizationCodeBroker());
 }
 /// <summary>
 /// Constructs a new authorization code for Windows Store application targeting an installed application flow.
 /// </summary>
 /// <param name="flow">An authorization code flow.</param>
 public AuthorizationCodeWPInstalledApp(IAuthorizationCodeFlow flow)
 {
 innerInstallApp = new AuthorizationCodeInstalledApp(flow, new AuthorizationCodeBroker());
 }
 #region IAuthorizationCodeInstalledApp Members
 public IAuthorizationCodeFlow Flow
 {
 get { return innerInstallApp.Flow; }
 }
 public ICodeReceiver CodeReceiver
 {
 get { return innerInstallApp.CodeReceiver; }
 }
 public async Task<UserCredential> AuthorizeAsync(string userId, CancellationToken taskCancellationToken)
 {
 return await innerInstallApp.AuthorizeAsync(userId, taskCancellationToken).ConfigureAwait(false);
 }
 #endregion
 }
 }