Keyguard sound needs to hold wake lock.

We need to hold a wakelock while playing the keyguard lock sound,
so that it actually completes before the CPU goes to sleep.

Change-Id: I144c345383afeb911ea461b2eb17b31183b6d092

media/java/android/media/Ringtone.java

@@ -203,7 +203,22 @@ public class Ringtone {
         mUri = uri;
         openMediaPlayer();
     }
-    
+
+    /** @hide */
+    public void setWakeMode(Context context, int mode) {
+        if (mAudio == null) {
+            try {
+                openMediaPlayer();
+            } catch (Exception ex) {
+                Log.e(TAG, "setWakeMode() caught ", ex);
+                mAudio = null;
+            }
+        }
+        if (mAudio != null) {
+            mAudio.setWakeMode(context, mode);
+        }
+    }
+
     /**
      * Plays the ringtone.
      */