some changes

src/Yavsc.Server/Models/Auth/GoogleCloudMobileDeclaration.cs

@@ -0,0 +1,44 @@
+using System;
+using System.ComponentModel.DataAnnotations;
+using System.ComponentModel.DataAnnotations.Schema;
+using Newtonsoft.Json;
+
+namespace Yavsc.Models.Identity
+{
+  [JsonObject]
+
+  public class GoogleCloudMobileDeclaration : IGCMDeclaration {
+
+    [Required]
+    public string GCMRegistrationId { get; set; }
+
+    [Key,Required]
+    public string DeviceId { get; set; }
+
+    public string Model { get; set; }
+    public string Platform { get; set; }
+    public string Version { get; set; }
+    public string DeviceOwnerId { get; set; }
+    public DateTime DeclarationDate { get; set; }
+
+    /// <summary>
+    /// Latest Activity Update
+    /// 
+    /// Let's says, 
+    /// the latest time this device downloaded functional info from server 
+    /// activity list, let's say, promoted ones, those thar are at index, and
+    /// all others, that are not listed as unsupported ones (not any more, after 
+    /// has been annonced as obsolete a decent laps of time).
+    /// 
+    /// In order to say, is any activity has changed here.
+    /// </summary>
+    /// <returns></returns>
+    public DateTime ? LatestActivityUpdate { get; set; }
+
+    [JsonIgnore,ForeignKey("DeviceOwnerId")]
+    public virtual ApplicationUser DeviceOwner { get; set; }
+
+
+  }
+
+}