Add slice provider to settings (only provides wifi for now)

- Adds a slice provider to settings that can make a wifi slice

Test: Use SliceBrowser to look at the slice
Bug: 68378569
Change-Id: I8c73ea96a99ee9b0db4a2d7fddc5dbc2b1156da8

res/layout/search_slice_item.xml

@@ -0,0 +1,34 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (C) 2017 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.
+-->
+
+<LinearLayout
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="match_parent"
+    android:layout_height="wrap_content"
+    android:minHeight="?android:attr/listPreferredItemHeight"
+    android:paddingTop="16dp"
+    android:paddingBottom="16dp"
+    android:paddingEnd="?android:attr/listPreferredItemPaddingEnd"
+    android:background="?android:attr/selectableItemBackground"
+    android:clipToPadding="false">
+
+    <include layout="@layout/search_icon_view"/>
+
+    <android.app.slice.widget.SliceView
+        android:id="@android:id/content"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"/>
+</LinearLayout>