AAudio: bump priority of AAudio Mixer to match FastMixer

Service RT thread should run at a slightly higher priority because
it generally does less work and is more critical.

Bug: 71817389
Test: Run an AAudio stream in SHARED mode.
Test:   adb shell ps -e -T -o uid,pid,tid,ppid,pri,ni,cmd| grep AAudio
Test: See bug for more test instructions.
Change-Id: I762af6ac1a9883d47b4c42bfe9f8455416251a12
diff --git a/services/oboeservice/AAudioService.h b/services/oboeservice/AAudioService.h
index d21b1cd..43a59c3 100644
--- a/services/oboeservice/AAudioService.h
+++ b/services/oboeservice/AAudioService.h
@@ -87,6 +87,10 @@
 
 private:
 
+    /** @return true if the client is the audioserver
+     */
+    bool isCallerInService();
+
     /**
      * Lookup stream and then validate access to the stream.
      * @param streamHandle
@@ -106,9 +110,10 @@
 
     aaudio::AAudioStreamTracker     mStreamTracker;
 
-    enum constants {
-        DEFAULT_AUDIO_PRIORITY = 2
-    };
+    // TODO  Extract the priority constants from services/audioflinger/Threads.cpp
+    // and share them with this code. Look for "kPriorityFastMixer".
+    static constexpr int32_t        kRealTimeAudioPriorityClient = 2;
+    static constexpr int32_t        kRealTimeAudioPriorityService = 3;
 };
 
 } /* namespace android */