Remove redundant field initialization in Java code.

components/gcm_driver/android/java/src/org/chromium/components/gcm_driver/GoogleCloudMessagingV2.java

 // Copyright 2014 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.components.gcm_driver;
 
 import android.app.PendingIntent;
 import android.content.Context;
 import android.content.Intent;
 import android.os.Bundle;
@@ skipping 25 matching lines @@
     private static final String ERROR_MAIN_THREAD = "MAIN_THREAD";
     private static final String ERROR_SERVICE_NOT_AVAILABLE = "SERVICE_NOT_AVAILABLE";
     private static final String EXTRA_DELETE = "delete";
     private static final String EXTRA_REGISTRATION_ID = "registration_id";
     private static final String EXTRA_SENDER = "sender";
     private static final String EXTRA_MESSENGER = "google.messenger";
     private static final String EXTRA_SUBTYPE = "subtype";
     private static final String EXTRA_SUBSCRIPTION = "subscription";
 
     private Context mContext;
-    private PendingIntent mAppPendingIntent = null;
+    private PendingIntent mAppPendingIntent;
     private final Object mAppPendingIntentLock = new Object();
 
     public GoogleCloudMessagingV2(Context context) {
         mContext = context;
     }
 
     @Override
     public String subscribe(String source, String subtype, @Nullable Bundle data)
             throws IOException {
         if (data == null) {
@@ skipping 131 matching lines @@
                 Intent target = new Intent();
                 // Fill in the package, to prevent the intent from being used.
                 target.setPackage("com.google.example.invalidpackage");
                 mAppPendingIntent = PendingIntent.getBroadcast(
                     mContext.getApplicationContext(), 0, target, 0);
             }
         }
         intent.putExtra(INTENT_PARAM_APP, mAppPendingIntent);
     }
 }