diff --git a/src/com/android/phone/CarrierConfigLoader.java b/src/com/android/phone/CarrierConfigLoader.java
index 4ff7316..e729d28 100644
--- a/src/com/android/phone/CarrierConfigLoader.java
+++ b/src/com/android/phone/CarrierConfigLoader.java
@@ -36,6 +36,7 @@
 import android.os.Bundle;
 import android.os.Handler;
 import android.os.IBinder;
+import android.os.Looper;
 import android.os.Message;
 import android.os.PersistableBundle;
 import android.os.Process;
@@ -55,6 +56,7 @@
 import android.util.LocalLog;
 import android.util.Log;
 
+import com.android.internal.annotations.VisibleForTesting;
 import com.android.internal.telephony.ICarrierConfigLoader;
 import com.android.internal.telephony.IccCardConstants;
 import com.android.internal.telephony.Phone;
@@ -201,6 +203,10 @@
     // 3. clearing config (e.g. due to sim removal)
     // 4. encountering bind or IPC error
     private class ConfigHandler extends Handler {
+        ConfigHandler(@NonNull Looper looper) {
+            super(looper);
+        }
+
         @Override
         public void handleMessage(Message msg) {
             final int phoneId = msg.arg1;
@@ -287,7 +293,7 @@
                         } else {
                             // Put a stub bundle in place so that the rest of the logic continues
                             // smoothly.
-                            mConfigFromDefaultApp[phoneId] = new PersistableBundle();
+                            mConfigFromDefaultApp[phoneId] = PersistableBundle.EMPTY;
                             // Send broadcast if bind fails.
                             notifySubscriptionInfoUpdater(phoneId);
                             // TODO: We *must* call unbindService even if bindService returns false.
@@ -372,7 +378,7 @@
                         broadcastConfigChangedIntent(phoneId);
                     }
                     // Put a stub bundle in place so that the rest of the logic continues smoothly.
-                    mConfigFromDefaultApp[phoneId] = new PersistableBundle();
+                    mConfigFromDefaultApp[phoneId] = PersistableBundle.EMPTY;
                     notifySubscriptionInfoUpdater(phoneId);
                     break;
                 }
@@ -419,7 +425,7 @@
                         } else {
                             // Put a stub bundle in place so that the rest of the logic continues
                             // smoothly.
-                            mConfigFromCarrierApp[phoneId] = new PersistableBundle();
+                            mConfigFromCarrierApp[phoneId] = PersistableBundle.EMPTY;
                             // Send broadcast if bind fails.
                             broadcastConfigChangedIntent(phoneId);
                             loge("Bind to carrier app: " + carrierPackageName + " fails");
@@ -504,7 +510,7 @@
                         broadcastConfigChangedIntent(phoneId);
                     }
                     // Put a stub bundle in place so that the rest of the logic continues smoothly.
-                    mConfigFromCarrierApp[phoneId] = new PersistableBundle();
+                    mConfigFromCarrierApp[phoneId] = PersistableBundle.EMPTY;
                     notifySubscriptionInfoUpdater(phoneId);
                     break;
                 }
@@ -666,11 +672,13 @@
      * Constructs a CarrierConfigLoader, registers it as a service, and registers a broadcast
      * receiver for relevant events.
      */
-    private CarrierConfigLoader(Context context) {
+    @VisibleForTesting
+    /* package */ CarrierConfigLoader(Context context,
+            SubscriptionInfoUpdater subscriptionInfoUpdater, @NonNull Looper looper) {
         mContext = context;
         mPlatformCarrierConfigPackage =
                 mContext.getString(R.string.platform_carrier_config_package);
-        mHandler = new ConfigHandler();
+        mHandler = new ConfigHandler(looper);
 
         IntentFilter bootFilter = new IntentFilter();
         bootFilter.addAction(Intent.ACTION_BOOT_COMPLETED);
@@ -690,7 +698,7 @@
         mConfigFromCarrierApp = new PersistableBundle[numPhones];
         mPersistentOverrideConfigs = new PersistableBundle[numPhones];
         mOverrideConfigs = new PersistableBundle[numPhones];
-        mNoSimConfig = new PersistableBundle();
+        mNoSimConfig = PersistableBundle.EMPTY;
         mServiceConnection = new CarrierServiceConnection[numPhones];
         mServiceBound = new boolean[numPhones];
         mHasSentConfigChange = new boolean[numPhones];
@@ -701,7 +709,7 @@
         TelephonyFrameworkInitializer
                 .getTelephonyServiceManager().getCarrierConfigServiceRegisterer().register(this);
         logd("CarrierConfigLoader has started");
-        mSubscriptionInfoUpdater = PhoneFactory.getSubscriptionInfoUpdater();
+        mSubscriptionInfoUpdater = subscriptionInfoUpdater;
         mHandler.sendEmptyMessage(EVENT_CHECK_SYSTEM_UPDATE);
     }
 
@@ -710,11 +718,11 @@
      *
      * This is only done once, at startup, from {@link com.android.phone.PhoneApp#onCreate}.
      */
-    /* package */
-    static CarrierConfigLoader init(Context context) {
+    /* package */ static CarrierConfigLoader init(Context context) {
         synchronized (CarrierConfigLoader.class) {
             if (sInstance == null) {
-                sInstance = new CarrierConfigLoader(context);
+                sInstance = new CarrierConfigLoader(context,
+                        PhoneFactory.getSubscriptionInfoUpdater(), Looper.myLooper());
             } else {
                 Log.wtf(LOG_TAG, "init() called multiple times!  sInstance = " + sInstance);
             }
@@ -722,7 +730,8 @@
         }
     }
 
-    private void clearConfigForPhone(int phoneId, boolean fetchNoSimConfig) {
+    @VisibleForTesting
+    /* package */ void clearConfigForPhone(int phoneId, boolean fetchNoSimConfig) {
         /* Ignore clear configuration request if device is being shutdown. */
         Phone phone = PhoneFactory.getPhone(phoneId);
         if (phone != null) {
@@ -759,7 +768,7 @@
         }
 
         if (configToSend == null) {
-            configToSend = new PersistableBundle();
+            configToSend = PersistableBundle.EMPTY;
         }
 
         // mOverrideConfigs is for testing. And it will override current configs.
@@ -844,7 +853,8 @@
         }
     }
 
-    private CarrierIdentifier getCarrierIdentifierForPhoneId(int phoneId) {
+    @VisibleForTesting
+    /* package */ CarrierIdentifier getCarrierIdentifierForPhoneId(int phoneId) {
         String mcc = "";
         String mnc = "";
         String imsi = "";
@@ -1000,12 +1010,14 @@
         }
     }
 
-    private void saveConfigToXml(String packageName, @NonNull String extraString, int phoneId,
+    @VisibleForTesting
+    /* package */ void saveConfigToXml(String packageName, @NonNull String extraString, int phoneId,
             CarrierIdentifier carrierId, PersistableBundle config) {
         saveConfigToXml(packageName, extraString, phoneId, carrierId, config, false);
     }
 
-    private void saveNoSimConfigToXml(String packageName, PersistableBundle config) {
+    @VisibleForTesting
+    /* package */ void saveNoSimConfigToXml(String packageName, PersistableBundle config) {
         saveConfigToXml(packageName, "", -1, null, config, true);
     }
 
@@ -1176,7 +1188,7 @@
             String callingFeatureId) {
         if (!TelephonyPermissions.checkCallingOrSelfReadPhoneState(mContext, subId, callingPackage,
                 callingFeatureId, "getCarrierConfig")) {
-            return new PersistableBundle();
+            return PersistableBundle.EMPTY;
         }
 
         int phoneId = SubscriptionManager.getPhoneId(subId);
@@ -1253,7 +1265,7 @@
     private void overrideConfig(@NonNull PersistableBundle[] currentOverrides, int phoneId,
             @Nullable PersistableBundle overrides) {
         if (overrides == null) {
-            currentOverrides[phoneId] = new PersistableBundle();
+            currentOverrides[phoneId] = PersistableBundle.EMPTY;
         } else if (currentOverrides[phoneId] == null) {
             currentOverrides[phoneId] = overrides;
         } else {
@@ -1315,6 +1327,31 @@
         return mPlatformCarrierConfigPackage;
     }
 
+    @VisibleForTesting
+    /* package */ Handler getHandler() {
+        return mHandler;
+    }
+
+    @VisibleForTesting
+    /* package */ PersistableBundle getConfigFromDefaultApp(int phoneId) {
+        return mConfigFromDefaultApp[phoneId];
+    }
+
+    @VisibleForTesting
+    /* package */ PersistableBundle getConfigFromCarrierApp(int phoneId) {
+        return mConfigFromCarrierApp[phoneId];
+    }
+
+    @VisibleForTesting
+     /* package */ PersistableBundle getNoSimConfig() {
+        return mNoSimConfig;
+    }
+
+    @VisibleForTesting
+    /* package */ PersistableBundle getOverrideConfig(int phoneId) {
+        return mOverrideConfigs[phoneId];
+    }
+
     private void unbindIfBound(Context context, CarrierServiceConnection conn,
             int phoneId) {
         if (mServiceBound[phoneId]) {