Add storage dashborad page.

Refactor shared dashboard page display logic between storage and
system page.

Bug: 31800690
Test: RunSettingsRoboTests

Change-Id: I7eb86f590b79ab871bdb383fb2f5326790beb193

res/xml/storage_dashboard_fragment.xml

@@ -0,0 +1,23 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (C) 2016 The Android Open Source Project
+
+     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.
+-->
+
+<PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android">
+    <com.android.settings.dashboard.DashboardTilePreference
+        android:key="pref_manage_storage"
+        android:title="@string/storage_menu_manage"
+        android:fragment="com.android.settings.deletionhelper.AutomaticStorageManagerSettings">
+    </com.android.settings.dashboard.DashboardTilePreference>
+</PreferenceScreen>