Merge changes I3ee2313c,Ibbf9eb2a

* changes:
  Remove divider line for battery card preference
  Add CardPreference in battery settings page

res/layout/card_preference_layout.xml

@@ -0,0 +1,30 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+  Copyright (C) 2019 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.
+  -->
+
+<FrameLayout
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="match_parent"
+    android:layout_height="wrap_content">
+    <com.google.android.material.card.MaterialCardView
+        android:id="@+id/container"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_margin="8dp"
+        style="@style/ContextualCardStyle">
+        <include layout="@layout/preference_material" />
+    </com.google.android.material.card.MaterialCardView>
+</FrameLayout>