MediaMetrics: Prepare statistics for protos

1) Add AudioRecord to Analytics trigger.
2) Log RecordThread statistics.
3) Rename DURATIONNS to EXECUTETIMENS to avoid confusion.
4) Use streamType from server not client.
5) Split MMAP types to MMAP_PLAYBACK and MMAP_CAPTURE.
6) Use string flags for AudioTrack and AudioRecord.
7) Compute underrun frames for MixerThread.
8) Log BT connection state.

Test: adb shell dumpsys media.metrics
Test: atest mediametrics_tests
Test: adb shell dumpsys stats --metadata
Bug: 149850236
Change-Id: Iacf3f117c00ec9f377e62862080252aef9dc084f
diff --git a/services/audioflinger/TrackMetrics.h b/services/audioflinger/TrackMetrics.h
index 399c788..12bd341 100644
--- a/services/audioflinger/TrackMetrics.h
+++ b/services/audioflinger/TrackMetrics.h
@@ -67,16 +67,21 @@
         mIntervalStartTimeNs = systemTime();
     }
 
-    void logConstructor(pid_t creatorPid, uid_t creatorUid) const {
+    void logConstructor(pid_t creatorPid, uid_t creatorUid,
+            audio_stream_type_t streamType = AUDIO_STREAM_DEFAULT) const {
         // Once this item is logged by the server, the client can add properties.
         // no lock required, all local or const variables.
-        mediametrics::LogItem(mMetricsId)
-            .setPid(creatorPid)
+        mediametrics::LogItem item(mMetricsId);
+        item.setPid(creatorPid)
             .setUid(creatorUid)
             .set(AMEDIAMETRICS_PROP_ALLOWUID, (int32_t)creatorUid)
             .set(AMEDIAMETRICS_PROP_EVENT,
-                    AMEDIAMETRICS_PROP_PREFIX_SERVER AMEDIAMETRICS_PROP_EVENT_VALUE_CTOR)
-            .record();
+                    AMEDIAMETRICS_PROP_PREFIX_SERVER AMEDIAMETRICS_PROP_EVENT_VALUE_CTOR);
+        // log streamType from the service, since client doesn't know chosen streamType.
+        if (streamType != AUDIO_STREAM_DEFAULT) {
+            item.set(AMEDIAMETRICS_PROP_STREAMTYPE, toString(streamType).c_str());
+        }
+        item.record();
     }
 
     // Called when we are removed from the Thread.