[Android] Remove unused class SyncOffPreference

Remove unused class SyncOffPreference and the resource xml file that
is only used in this class.

Bug: 1139896
Change-Id: I0ce6ecf5203f8c682e4f965ffe66e57204dcf5c4
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2484450Reviewed-by: Marc Treib <treib@chromium.org>
Reviewed-by: Theresa  <twellington@chromium.org>
Commit-Queue: Tanmoy Mollik <triploblastic@chromium.org>
Cr-Commit-Position: refs/heads/master@{#819818}

chrome/android/chrome_java_resources.gni

@@ -940,7 +940,6 @@ chrome_java_resources = [
   "java/res/layout/personalized_signin_promo_view_settings.xml",
   "java/res/layout/powered_by_chrome_footer.xml",
   "java/res/layout/preference_text_scale.xml",
-  "java/res/layout/preference_turn_off_sync.xml",
   "java/res/layout/radio_button_group_homepage_preference.xml",
   "java/res/layout/radio_button_group_theme_preference.xml",
   "java/res/layout/recent_tabs_group_item.xml",

chrome/android/chrome_java_sources.gni

@@ -1476,7 +1476,6 @@ chrome_java_sources = [
   "java/src/org/chromium/chrome/browser/sync/settings/SignInPreference.java",
   "java/src/org/chromium/chrome/browser/sync/settings/SyncAndServicesSettings.java",
   "java/src/org/chromium/chrome/browser/sync/settings/SyncErrorCardPreference.java",
-  "java/src/org/chromium/chrome/browser/sync/settings/SyncOffPreference.java",
   "java/src/org/chromium/chrome/browser/sync/settings/SyncPromoPreference.java",
   "java/src/org/chromium/chrome/browser/sync/settings/SyncSettingsUtils.java",
   "java/src/org/chromium/chrome/browser/sync/ui/PassphraseActivity.java",

chrome/android/java/res/layout/preference_turn_off_sync.xml

-<?xml version="1.0" encoding="utf-8"?>
-<!-- Copyright 2020 The Chromium Authors. All rights reserved.
-     Use of this source code is governed by a BSD-style license that can be
-     found in the LICENSE file. -->
-
-<LinearLayout
-    xmlns:android="http://schemas.android.com/apk/res/android"
-    style="@style/PreferenceLayout"
-    android:layout_width="match_parent"
-    android:layout_height="wrap_content"
-    android:gravity="center">
-
-    <TextView
-        android:id="@+id/turn_off_sync"
-        android:layout_width="match_parent"
-        android:layout_height="wrap_content"
-        android:text="@string/turn_off_sync"
-        android:textAppearance="@style/TextAppearance.TextMediumThick.Blue"
-        android:gravity="center"/>
-
-</LinearLayout>

chrome/android/java/src/org/chromium/chrome/browser/sync/settings/SyncOffPreference.java

-// Copyright 2020 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-package org.chromium.chrome.browser.sync.settings;
-
-import android.content.Context;
-import android.util.AttributeSet;
-
-import androidx.preference.DialogPreference;
-
-import org.chromium.chrome.R;
-
-/**
- * A preference that displays "Sign out and turn off sync" button in {@link ManageSyncSettings}.
- */
-public class SyncOffPreference extends DialogPreference {
-    public SyncOffPreference(Context context, AttributeSet attrs) {
-        super(context, attrs);
-
-        setLayoutResource(R.layout.preference_turn_off_sync);
-    }
-}