diff --git a/res/values/strings.xml b/res/values/strings.xml
index 533c130..21bec16 100644
--- a/res/values/strings.xml
+++ b/res/values/strings.xml
@@ -10041,6 +10041,9 @@
     <!-- Title for HFP(hands free profile) output switch button in settings. -->
     <string name="take_call_on_title">Take call on</string>
 
+    <!-- Toast that appears when users tap an APN for which parameters cannot be viewed. [CHAR LIMIT=NONE] -->
+    <string name="cannot_change_apn_toast">This APN cannot be changed.</string>
+
     <!--  Title for battery Suggestion. (tablet) [CHAR LIMIT=46] -->
     <string name="battery_suggestion_title" product="tablet" >Improve tablet\'s battery life</string>
     <!--  Title for battery Suggestion. (device) [CHAR LIMIT=46] -->
diff --git a/src/com/android/settings/datetime/timezone/model/FilteredCountryTimeZones.java b/src/com/android/settings/datetime/timezone/model/FilteredCountryTimeZones.java
index 858c8eb..6af0911 100644
--- a/src/com/android/settings/datetime/timezone/model/FilteredCountryTimeZones.java
+++ b/src/com/android/settings/datetime/timezone/model/FilteredCountryTimeZones.java
@@ -16,7 +16,7 @@
 
 package com.android.settings.datetime.timezone.model;
 
-import libcore.util.CountryTimeZones;
+import libcore.timezone.CountryTimeZones;
 
 import java.util.Collections;
 import java.util.List;
diff --git a/src/com/android/settings/datetime/timezone/model/TimeZoneData.java b/src/com/android/settings/datetime/timezone/model/TimeZoneData.java
index c914845..61244f2 100644
--- a/src/com/android/settings/datetime/timezone/model/TimeZoneData.java
+++ b/src/com/android/settings/datetime/timezone/model/TimeZoneData.java
@@ -18,9 +18,9 @@
 import androidx.annotation.VisibleForTesting;
 import androidx.collection.ArraySet;
 
-import libcore.util.CountryTimeZones;
-import libcore.util.CountryZonesFinder;
-import libcore.util.TimeZoneFinder;
+import libcore.timezone.CountryTimeZones;
+import libcore.timezone.CountryZonesFinder;
+import libcore.timezone.TimeZoneFinder;
 
 import java.lang.ref.WeakReference;
 import java.util.Collections;
diff --git a/src/com/android/settings/deviceinfo/PrivateVolumeOptionMenuController.java b/src/com/android/settings/deviceinfo/PrivateVolumeOptionMenuController.java
index 6047f8c..75fc73b 100644
--- a/src/com/android/settings/deviceinfo/PrivateVolumeOptionMenuController.java
+++ b/src/com/android/settings/deviceinfo/PrivateVolumeOptionMenuController.java
@@ -68,7 +68,8 @@
         if (migrate != null) {
             migrate.setVisible((privateVol != null)
                     && (privateVol.getType() == VolumeInfo.TYPE_PRIVATE)
-                    && !Objects.equals(mVolumeInfo, privateVol));
+                    && !Objects.equals(mVolumeInfo, privateVol)
+                    && privateVol.isMountedWritable());
         }
     }
 
diff --git a/src/com/android/settings/deviceinfo/PrivateVolumeSettings.java b/src/com/android/settings/deviceinfo/PrivateVolumeSettings.java
index 54e0eef..7fcedb7 100644
--- a/src/com/android/settings/deviceinfo/PrivateVolumeSettings.java
+++ b/src/com/android/settings/deviceinfo/PrivateVolumeSettings.java
@@ -415,7 +415,8 @@
                 .getPrimaryStorageCurrentVolume();
         migrate.setVisible((privateVol != null)
                 && (privateVol.getType() == VolumeInfo.TYPE_PRIVATE)
-                && !Objects.equals(mVolume, privateVol));
+                && !Objects.equals(mVolume, privateVol)
+                && privateVol.isMountedWritable());
     }
 
     @Override
diff --git a/src/com/android/settings/network/ApnEditor.java b/src/com/android/settings/network/ApnEditor.java
index 86e9f7b..0cc88b3 100644
--- a/src/com/android/settings/network/ApnEditor.java
+++ b/src/com/android/settings/network/ApnEditor.java
@@ -166,7 +166,7 @@
             Telephony.Carriers.ROAMING_PROTOCOL, // 20
             Telephony.Carriers.MVNO_TYPE,   // 21
             Telephony.Carriers.MVNO_MATCH_DATA,  // 22
-            Telephony.Carriers.EDITED,   // 23
+            Telephony.Carriers.EDITED_STATUS,   // 23
             Telephony.Carriers.USER_EDITABLE    //24
     };
 
@@ -1030,7 +1030,7 @@
                 callUpdate,
                 CARRIER_ENABLED_INDEX);
 
-        values.put(Telephony.Carriers.EDITED, Telephony.Carriers.USER_EDITED);
+        values.put(Telephony.Carriers.EDITED_STATUS, Telephony.Carriers.USER_EDITED);
 
         if (callUpdate) {
             final Uri uri = mApnData.getUri() == null ? mCarrierUri : mApnData.getUri();
diff --git a/src/com/android/settings/network/ApnPreference.java b/src/com/android/settings/network/ApnPreference.java
index 27d275f..73837af 100755
--- a/src/com/android/settings/network/ApnPreference.java
+++ b/src/com/android/settings/network/ApnPreference.java
@@ -29,6 +29,7 @@
 import android.view.View;
 import android.widget.CompoundButton;
 import android.widget.RadioButton;
+import android.widget.Toast;
 
 import com.android.settings.R;
 
@@ -53,6 +54,7 @@
     private static CompoundButton mCurrentChecked = null;
     private boolean mProtectFromCheckedChange = false;
     private boolean mSelectable = true;
+    private boolean mHideDetails = false;
 
     @Override
     public void onBindViewHolder(PreferenceViewHolder view) {
@@ -112,6 +114,11 @@
         super.onClick();
         Context context = getContext();
         if (context != null) {
+            if (mHideDetails) {
+                Toast.makeText(context, context.getString(
+                        R.string.cannot_change_apn_toast), Toast.LENGTH_LONG).show();
+                return;
+            }
             int pos = Integer.parseInt(getKey());
             Uri url = ContentUris.withAppendedId(Telephony.Carriers.CONTENT_URI, pos);
             Intent editIntent = new Intent(Intent.ACTION_EDIT, url);
@@ -131,4 +138,8 @@
     public void setSubId(int subId) {
         mSubId = subId;
     }
+
+    public void setHideDetails() {
+        mHideDetails = true;
+    }
 }
diff --git a/src/com/android/settings/network/ApnSettings.java b/src/com/android/settings/network/ApnSettings.java
index 5bc52cc..3b39e38 100755
--- a/src/com/android/settings/network/ApnSettings.java
+++ b/src/com/android/settings/network/ApnSettings.java
@@ -77,12 +77,23 @@
     public static final String MVNO_TYPE = "mvno_type";
     public static final String MVNO_MATCH_DATA = "mvno_match_data";
 
+    private static final String[] CARRIERS_PROJECTION = new String[] {
+            Telephony.Carriers._ID,
+            Telephony.Carriers.NAME,
+            Telephony.Carriers.APN,
+            Telephony.Carriers.TYPE,
+            Telephony.Carriers.MVNO_TYPE,
+            Telephony.Carriers.MVNO_MATCH_DATA,
+            Telephony.Carriers.EDITED_STATUS,
+    };
+
     private static final int ID_INDEX = 0;
     private static final int NAME_INDEX = 1;
     private static final int APN_INDEX = 2;
     private static final int TYPES_INDEX = 3;
     private static final int MVNO_TYPE_INDEX = 4;
     private static final int MVNO_MATCH_DATA_INDEX = 5;
+    private static final int EDITED_INDEX = 6;
 
     private static final int MENU_NEW = Menu.FIRST;
     private static final int MENU_RESTORE = Menu.FIRST + 1;
@@ -115,6 +126,7 @@
 
     private boolean mHideImsApn;
     private boolean mAllowAddingApns;
+    private boolean mHidePresetApnDetails;
 
     public ApnSettings() {
         super(UserManager.DISALLOW_CONFIG_MOBILE_NETWORKS);
@@ -195,6 +207,7 @@
                 mAllowAddingApns = false;
             }
         }
+        mHidePresetApnDetails = b.getBoolean(CarrierConfigManager.KEY_HIDE_PRESET_APN_DETAILS_BOOL);
         mUserManager = UserManager.get(activity);
     }
 
@@ -276,9 +289,8 @@
             where.append(" AND NOT (type='ims')");
         }
 
-        Cursor cursor = getContentResolver().query(Telephony.Carriers.CONTENT_URI, new String[] {
-                "_id", "name", "apn", "type", "mvno_type", "mvno_match_data"}, where.toString(),
-                null, Telephony.Carriers.DEFAULT_SORT_ORDER);
+        Cursor cursor = getContentResolver().query(Telephony.Carriers.CONTENT_URI,
+                CARRIERS_PROJECTION, where.toString(), null, Telephony.Carriers.DEFAULT_SORT_ORDER);
 
         if (cursor != null) {
             IccRecords r = null;
@@ -303,14 +315,19 @@
                 String type = cursor.getString(TYPES_INDEX);
                 String mvnoType = cursor.getString(MVNO_TYPE_INDEX);
                 String mvnoMatchData = cursor.getString(MVNO_MATCH_DATA_INDEX);
+                int edited = cursor.getInt(EDITED_INDEX);
 
                 ApnPreference pref = new ApnPreference(getPrefContext());
 
                 pref.setKey(key);
                 pref.setTitle(name);
-                pref.setSummary(apn);
                 pref.setPersistent(false);
                 pref.setSubId(subId);
+                if (mHidePresetApnDetails && edited == Telephony.Carriers.UNEDITED) {
+                    pref.setHideDetails();
+                } else {
+                    pref.setSummary(apn);
+                }
 
                 boolean selectable = ((type == null) || !type.equals("mms"));
                 pref.setSelectable(selectable);
diff --git a/tests/robotests/src/com/android/settings/datetime/timezone/FixedOffsetPickerTest.java b/tests/robotests/src/com/android/settings/datetime/timezone/FixedOffsetPickerTest.java
index 9d650cc..00e36f9 100644
--- a/tests/robotests/src/com/android/settings/datetime/timezone/FixedOffsetPickerTest.java
+++ b/tests/robotests/src/com/android/settings/datetime/timezone/FixedOffsetPickerTest.java
@@ -22,7 +22,7 @@
 import com.android.settings.datetime.timezone.model.TimeZoneData;
 import com.android.settings.testutils.SettingsRobolectricTestRunner;
 
-import libcore.util.CountryZonesFinder;
+import libcore.timezone.CountryZonesFinder;
 
 import org.junit.Before;
 import org.junit.Test;
diff --git a/tests/robotests/src/com/android/settings/datetime/timezone/RegionSearchPickerTest.java b/tests/robotests/src/com/android/settings/datetime/timezone/RegionSearchPickerTest.java
index 02a3122..8810a9f 100644
--- a/tests/robotests/src/com/android/settings/datetime/timezone/RegionSearchPickerTest.java
+++ b/tests/robotests/src/com/android/settings/datetime/timezone/RegionSearchPickerTest.java
@@ -33,7 +33,7 @@
 import com.android.settings.datetime.timezone.model.TimeZoneData;
 import com.android.settings.testutils.SettingsRobolectricTestRunner;
 
-import libcore.util.CountryZonesFinder;
+import libcore.timezone.CountryZonesFinder;
 
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/tests/robotests/src/com/android/settings/datetime/timezone/model/TimeZoneDataTest.java b/tests/robotests/src/com/android/settings/datetime/timezone/model/TimeZoneDataTest.java
index 0359cfc..05cf6e5 100644
--- a/tests/robotests/src/com/android/settings/datetime/timezone/model/TimeZoneDataTest.java
+++ b/tests/robotests/src/com/android/settings/datetime/timezone/model/TimeZoneDataTest.java
@@ -26,9 +26,9 @@
 import org.junit.Test;
 import org.junit.runner.RunWith;
 
-import libcore.util.CountryTimeZones;
-import libcore.util.CountryTimeZones.TimeZoneMapping;
-import libcore.util.CountryZonesFinder;
+import libcore.timezone.CountryTimeZones;
+import libcore.timezone.CountryTimeZones.TimeZoneMapping;
+import libcore.timezone.CountryZonesFinder;
 
 import java.util.ArrayList;
 import java.util.Arrays;
diff --git a/tests/robotests/src/com/android/settings/deviceinfo/PrivateVolumeOptionMenuControllerTest.java b/tests/robotests/src/com/android/settings/deviceinfo/PrivateVolumeOptionMenuControllerTest.java
index 5f250dd..7b9b7b8 100644
--- a/tests/robotests/src/com/android/settings/deviceinfo/PrivateVolumeOptionMenuControllerTest.java
+++ b/tests/robotests/src/com/android/settings/deviceinfo/PrivateVolumeOptionMenuControllerTest.java
@@ -62,6 +62,7 @@
         MockitoAnnotations.initMocks(this);
 
         when(mVolumeInfo.getType()).thenReturn(VolumeInfo.TYPE_PRIVATE);
+        when(mVolumeInfo.isMountedWritable()).thenReturn(true);
         when(mPrimaryInfo.getType()).thenReturn(VolumeInfo.TYPE_PRIVATE);
         when(mMenu.findItem(anyInt())).thenReturn(mMigrateMenuItem);
         when(mMigrateMenuItem.getItemId()).thenReturn(100);
@@ -80,6 +81,7 @@
     @Test
     public void testMigrateDataIsNotVisibleNormally() {
         when(mPm.getPrimaryStorageCurrentVolume()).thenReturn(mPrimaryInfo);
+        when(mPrimaryInfo.isMountedWritable()).thenReturn(true);
 
         mController.onCreateOptionsMenu(mMenu, mMenuInflater);
         mController.onPrepareOptionsMenu(mMenu);
@@ -98,6 +100,17 @@
     }
 
     @Test
+    public void testMigrateDataIsNotVisibleWhenExternalVolumeIsNotMounted() {
+        when(mPm.getPrimaryStorageCurrentVolume()).thenReturn(mVolumeInfo);
+        when(mVolumeInfo.isMountedWritable()).thenReturn(false);
+
+        mController.onCreateOptionsMenu(mMenu, mMenuInflater);
+        mController.onPrepareOptionsMenu(mMenu);
+
+        verify(mMigrateMenuItem).setVisible(false);
+    }
+
+    @Test
     public void testMigrateDataGoesToMigrateWizard() {
         when(mPm.getPrimaryStorageCurrentVolume()).thenReturn(mVolumeInfo);
 
diff --git a/tests/robotests/src/com/android/settings/testutils/shadow/ShadowLibcoreTimeZoneNames.java b/tests/robotests/src/com/android/settings/testutils/shadow/ShadowLibcoreTimeZoneNames.java
deleted file mode 100644
index 7292234..0000000
--- a/tests/robotests/src/com/android/settings/testutils/shadow/ShadowLibcoreTimeZoneNames.java
+++ /dev/null
@@ -1,60 +0,0 @@
-/*
- * Copyright (C) 2016 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.
- */
-
-package com.android.settings.testutils.shadow;
-
-import libcore.icu.TimeZoneNames;
-
-import org.robolectric.annotation.Implementation;
-import org.robolectric.annotation.Implements;
-import org.robolectric.annotation.RealObject;
-import org.robolectric.util.ReflectionHelpers;
-
-import java.util.Locale;
-import java.util.TimeZone;
-
-/**
- * System.logI used by ZoneStringsCache.create is a method new in API 24 and not available in
- * Robolectric's 6.0 jar. Create a shadow which removes that log call.
- */
-@Implements(value = TimeZoneNames.class, isInAndroidSdk = false)
-public class ShadowLibcoreTimeZoneNames {
-
-    private static final String[] availableTimeZoneIds = TimeZone.getAvailableIDs();
-
-    @Implements(value = TimeZoneNames.ZoneStringsCache.class, isInAndroidSdk = false)
-    public static class ShadowZoneStringsCache {
-
-        @RealObject
-        private TimeZoneNames.ZoneStringsCache mRealObject;
-
-        @Implementation
-        public String[][] create(Locale locale) {
-            // Set up the 2D array used to hold the names. The first column contains the Olson ids.
-            String[][] result = new String[availableTimeZoneIds.length][5];
-            for (int i = 0; i < availableTimeZoneIds.length; ++i) {
-                result[i][0] = availableTimeZoneIds[i];
-            }
-
-            ReflectionHelpers.callInstanceMethod(TimeZoneNames.class,
-                    mRealObject, "fillZoneStrings",
-                    ReflectionHelpers.ClassParameter.from(String.class, locale.toLanguageTag()),
-                    ReflectionHelpers.ClassParameter.from(String[][].class, result));
-
-            return result;
-        }
-    }
-}