MediaMetrics: Use AllowUid property for services to control client access

Remove implicit first client uid access.

Test: adb shell dumpsys media.metrics
Bug: 149850236
Change-Id: I4f953db4688bf5f174c3e1611f492f31d2926e96
diff --git a/media/libmediametrics/include/MediaMetricsConstants.h b/media/libmediametrics/include/MediaMetricsConstants.h
index a7e79f4..00da69a 100644
--- a/media/libmediametrics/include/MediaMetricsConstants.h
+++ b/media/libmediametrics/include/MediaMetricsConstants.h
@@ -86,6 +86,7 @@
 // of suppressed in the Time Machine.
 #define AMEDIAMETRICS_PROP_SUFFIX_CHAR_DUPLICATES_ALLOWED '#'
 
+#define AMEDIAMETRICS_PROP_ALLOWUID       "_allowUid"      // int32_t, allow client uid to post
 #define AMEDIAMETRICS_PROP_AUXEFFECTID    "auxEffectId"    // int32 (AudioTrack)
 #define AMEDIAMETRICS_PROP_BUFFERSIZEFRAMES "bufferSizeFrames" // int32
 #define AMEDIAMETRICS_PROP_BUFFERCAPACITYFRAMES "bufferCapacityFrames" // int32