Use SettingsLib's MainSwitchPreference to replace the Switches which use

LayoutPreference.

Bug: 175181773
Test: Run robotest and apply the widget in Settings and see the ui
Change-Id: I4588d1fc3004970b174e7c5c5d1aa7745f774985

res/layout/emergency_gesture_switch_bar.xml

@@ -1,39 +0,0 @@
-<?xml version="1.0" encoding="utf-8"?>
-<!--
-  ~ Copyright (C) 2020 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.
-  -->
-
-<!-- For use in a LayoutPreference -->
-<LinearLayout
-    xmlns:android="http://schemas.android.com/apk/res/android"
-    android:layout_height="wrap_content"
-    android:layout_width="match_parent"
-    android:orientation="vertical"
-    android:importantForAccessibility="no">
-
-    <com.android.settings.widget.SwitchBar
-        android:id="@+id/switch_bar"
-        android:minHeight="?android:attr/actionBarSize"
-        android:layout_height="wrap_content"
-        android:layout_width="match_parent"
-        android:paddingStart="0dp"
-        android:theme="?attr/switchBarTheme"/>
-    <TextView
-        android:layout_height="wrap_content"
-        android:layout_width="match_parent"
-        android:layout_marginStart="@dimen/actionbar_subsettings_contentInsetStart"
-        android:layout_marginVertical="16dp"
-        android:text="@string/emergency_gesture_screen_summary"/>
-</LinearLayout>