move some xamarin specific services to app proj

src/App/Services/MobileStorageService.cs

@@ -0,0 +1,53 @@
+using Bit.Core;
+using Bit.Core.Abstractions;
+using System.Collections.Generic;
+using System.Threading.Tasks;
+
+namespace Bit.App.Services
+{
+    public class MobileStorageService : IStorageService
+    {
+        private readonly IStorageService _preferencesStorageService;
+        private readonly IStorageService _liteDbStorageService;
+
+        private readonly HashSet<string> _preferenceStorageKeys = new HashSet<string>
+        {
+            Constants.LockOptionKey
+        };
+
+        public MobileStorageService(
+            IStorageService preferenceStorageService,
+            IStorageService liteDbStorageService)
+        {
+            _preferencesStorageService = preferenceStorageService;
+            _liteDbStorageService = liteDbStorageService;
+        }
+
+        public Task<T> GetAsync<T>(string key)
+        {
+            if(_preferenceStorageKeys.Contains(key))
+            {
+                return _preferencesStorageService.GetAsync<T>(key);
+            }
+            return _liteDbStorageService.GetAsync<T>(key);
+        }
+
+        public Task SaveAsync<T>(string key, T obj)
+        {
+            if(_preferenceStorageKeys.Contains(key))
+            {
+                return _preferencesStorageService.SaveAsync(key, obj);
+            }
+            return _liteDbStorageService.SaveAsync(key, obj);
+        }
+
+        public Task RemoveAsync(string key)
+        {
+            if(_preferenceStorageKeys.Contains(key))
+            {
+                return _preferencesStorageService.RemoveAsync(key);
+            }
+            return _liteDbStorageService.RemoveAsync(key);
+        }
+    }
+}