Reimplement OAuth2 library - Step 1

Src/GoogleApis/Apis/Util/IClock.cs

+/*
+Copyright 2013 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;
+
+namespace Google.Apis.Util
+{
+/// <summary>Clock wrapper for getting the current time.</summary>
+public interface IClock
+{
+/// <summary>
+/// Gets a <seealso cref="DateTime"/> object that is set to the current
date and time on this computer,·
+/// expressed as the local time.
+/// </summary>
+DateTime Now { get; }
+}
+
+/// <summary>A default clock implementation that wraps the <seealso cref="Da
teTime.Now"/> property.</summary>
+public class SystemClock : IClock
+{
+/// <summary>Constructs a new system clock.</summary>
+protected SystemClock() { }
+
+/// <summary>The default instance.</summary>
+public static readonly IClock Default = new SystemClock();
+
+public DateTime Now
+{
+get { return DateTime.Now; }
+}
+}
+}