[Provider Model] Carrie Wi-Fi offload toggle request

- Remove the Advanced expandable list pattern and expose the items

- Add Carrie Wi-Fi offload toggle preference

- Add Carrier Wi-Fi network preference

- Do not set Carrier Network together when setting Mobile Data, if
carrner network provision enabled.

- Screenshot:
  https://screenshot.googleplex.com/8vMow53cvGfUAoj

Bug: 182324921
Test: manual test
atest -c CarrierWifiTogglePreferenceControllerTest \
         MobileDataPreferenceControllerTest \
	 WifiPickerTrackerHelperTest

Change-Id: I5a7f4cc6850fe76c0efee392c0c0c23cb41f5e1e

res/values/strings.xml

@@ -13092,6 +13092,12 @@
     <string name="to_switch_networks_disconnect_ethernet">To switch networks, disconnect ethernet</string>
     <!-- Panel subtitle for Wi-Fi turned on. [CHAR LIMIT=60] -->
     <string name="wifi_is_turned_on_subtitle">Wi\u2011Fi is turned on</string>
+    <!-- Title for merged carrier Wi-Fi offload toggle. [CHAR LIMIT=NONE] -->
+    <string name="carrier_wifi_offload_title">W+ connections</string>
+    <!-- Summary for merged carrier Wi-Fi offload toggle. [CHAR LIMIT=NONE] -->
+    <string name="carrier_wifi_offload_summary">Allow Google Fi to use W+ networks to improve speed and coverage</string>
+    <!-- Title for merged carrier Wi-Fi network information. [CHAR LIMIT=NONE] -->
+    <string name="carrier_wifi_network_title">W+ network</string>
 
     <!-- Summary text separator for preferences including a short description
          (eg. "Connected / 5G"). [CHAR LIMIT=50] -->

res/xml/mobile_network_settings.xml

@@ -16,8 +16,7 @@
 <PreferenceScreen
     xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:settings="http://schemas.android.com/apk/res-auto"
-    android:key="mobile_network_pref_screen"
-    settings:initialExpandedChildrenCount="8">
+    android:key="mobile_network_pref_screen">
 
     <com.android.settings.widget.SettingsMainSwitchPreference
         android:key="use_sim_switch"
@@ -78,6 +77,16 @@
             android:title="@string/billing_cycle"
             settings:controller="com.android.settings.datausage.BillingCyclePreferenceController"/>
 
+        <SwitchPreference
+            android:key="carrier_wifi_toggle"
+            android:title="@string/carrier_wifi_offload_title"
+            android:summary="@string/carrier_wifi_offload_summary"
+            settings:controller="com.android.settings.network.CarrierWifiTogglePreferenceController"/>
+
+        <Preference
+            android:key="carrier_wifi_network"
+            android:title="@string/carrier_wifi_network_title"/>
+
         <SwitchPreference
             android:key="mms_message"
             android:title="@string/mms_message_title"