[Android] Simplify "network predictions" preference to a boolean value.

chrome/android/java/res/xml/privacy_preferences.xml

 <?xml version="1.0" encoding="utf-8"?>
 <!-- Copyright 2015 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. -->
 
 <PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android">
     <org.chromium.chrome.browser.preferences.ChromeBaseCheckBoxPreference
         android:key="navigation_error"
         android:title="@string/navigation_error_title"
         android:summary="@string/navigation_error_summary"
         android:defaultValue="true" />
     <org.chromium.chrome.browser.preferences.ChromeBaseCheckBoxPreference
         android:key="search_suggestions"
         android:title="@string/search_suggestions_title"
         android:summary="@string/search_suggestions_summary"
         android:defaultValue="true" />
     <org.chromium.chrome.browser.preferences.ChromeBaseCheckBoxPreference
         android:key="safe_browsing_extended_reporting"
         android:title="@string/safe_browsing_extended_reporting_title"
         android:summary="@string/safe_browsing_extended_reporting_summary" />
     <org.chromium.chrome.browser.preferences.ChromeBaseCheckBoxPreference
         android:key="safe_browsing"
         android:title="@string/safe_browsing_title"
         android:summary="@string/safe_browsing_summary" />
-
-    <!-- Only one of these network prediction preferences will be shown, depending on whether
-         the device has cellular support. -->
-    <org.chromium.chrome.browser.preferences.privacy.NetworkPredictionPreference
+    <org.chromium.chrome.browser.preferences.ChromeBaseCheckBoxPreference
         android:key="network_predictions"
         android:title="@string/network_predictions_title"
-        android:persistent="false"
-        android:entries="@array/bandwidth_entries"
-        android:entryValues="@array/bandwidth_entry_values"
-        android:defaultValue="@string/network_prediction_wifi_only_value" />
-    <org.chromium.chrome.browser.preferences.ChromeBaseCheckBoxPreference
-        android:key="network_predictions_no_cellular"
-        android:title="@string/network_predictions_title"
-        android:summary="@string/network_predictions_summary"
-        android:defaultValue="true" />
+        android:persistent="false" />
 
     <!-- Only one of these "Usage and crash reports" preferences will be shown, depending on whether
          the device has cellular support. -->
     <org.chromium.chrome.browser.preferences.privacy.CrashDumpUploadPreference
         android:key="crash_dump_upload"
         android:title="@string/crash_dump_upload_title"
         android:entries="@array/crash_upload_entries"
         android:entryValues="@array/crash_upload_values"
         android:defaultValue="@string/crash_dump_never_upload_value" />
     <org.chromium.chrome.browser.preferences.ChromeBaseCheckBoxPreference
@@ skipping 16 matching lines @@
     <Preference
         android:key="physical_web"
         android:title="@string/physical_web_pref_title"
         android:fragment="org.chromium.chrome.browser.preferences.privacy.PhysicalWebPreferenceFragment" />
     <Preference
         android:key="clear_browsing_data"
         android:title="@string/clear_browsing_data_title"
         android:summary="@string/clear_browsing_data_summary"
         android:fragment="org.chromium.chrome.browser.preferences.privacy.ClearBrowsingDataPreferences" />
 </PreferenceScreen>