AudioService: add scheduleLoadSoundEffects

Instead of instantly loading sound effects during onSystemReady(), move
it to a protected method such that sub-classes can override it and
schedule to load it at a later time.

Bug: 129433717
Test: Build Taimen, sound effect still comes in at boot
Change-Id: Ic0e4e963df23392fc9d5dd1b1fea9a62020530ac

services/core/java/com/android/server/audio/AudioService.java

@@ -855,8 +855,7 @@ public class AudioService extends IAudioService.Stub
 
     public void onSystemReady() {
         mSystemReady = true;
-        sendMsg(mAudioHandler, MSG_LOAD_SOUND_EFFECTS, SENDMSG_QUEUE,
-                0, 0, null, 0);
+        scheduleLoadSoundEffects();
 
         mDeviceBroker.onSystemReady();
 
@@ -3224,6 +3223,14 @@ public class AudioService extends IAudioService.Stub
         return (reply.mStatus == 0);
     }
 
+    /**
+     * Schedule loading samples into the soundpool.
+     * This method can be overridden to schedule loading at a later time.
+     */
+    protected void scheduleLoadSoundEffects() {
+        sendMsg(mAudioHandler, MSG_LOAD_SOUND_EFFECTS, SENDMSG_QUEUE, 0, 0, null, 0);
+    }
+
     /**
      *  Unloads samples from the sound pool.
      *  This method can be called to free some memory when