Messaging: Further code improvements

* Remove redundant casts
* getParcelable(ArrayList|Exra) without class argument is deprecated
* ViewPager.setOnPageChangeListener -> addOnPageChangeListener
* RecyclerView.setOnScrollListener -> addOnScrollListener
* Remove unused initializations
* Remove unused code

Change-Id: I21beb6c90c675a4f2cfd7e3d5ebbd18b745f5911

src/com/android/messaging/util/NotificationPlayer.java

@@ -186,7 +186,7 @@ public class NotificationPlayer implements OnCompletionListener {
         @Override
         public void run() {
             while (true) {
-                Command cmd = null;
+                Command cmd;
 
                 synchronized (mCmdQueue) {
                     if (mDebug) {
@@ -327,31 +327,6 @@ public class NotificationPlayer implements OnCompletionListener {
         }
     }
 
-    /**
-     * We want to hold a wake lock while we do the prepare and play.  The stop probably is
-     * optional, but it won't hurt to have it too.  The problem is that if you start a sound
-     * while you're holding a wake lock (e.g. an alarm starting a notification), you want the
-     * sound to play, but if the CPU turns off before mThread gets to work, it won't.  The
-     * simplest way to deal with this is to make it so there is a wake lock held while the
-     * thread is starting or running.  You're going to need the WAKE_LOCK permission if you're
-     * going to call this.
-     *
-     * This must be called before the first time play is called.
-     *
-     * @hide
-     */
-    public void setUsesWakeLock() {
-        if (mWakeLock != null || mThread != null) {
-            // if either of these has happened, we've already played something.
-            // and our releases will be out of sync.
-            throw new RuntimeException("assertion failed mWakeLock=" + mWakeLock
-                    + " mThread=" + mThread);
-        }
-        final PowerManager pm = (PowerManager) Factory.get().getApplicationContext()
-                .getSystemService(Context.POWER_SERVICE);
-        mWakeLock = pm.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK, mTag);
-    }
-
     private void acquireWakeLock() {
         if (mWakeLock != null) {
             mWakeLock.acquire();