AudioFlinger: Add latency measurements from timestamp

Replaces main and aux buf from track dump.

Bug: 80272001
Test: adb shell dumpsys media.audio_flinger
Change-Id: I5d6565410e652ec7fc6701b171d299dea9f7bc3e
diff --git a/services/audioflinger/FastMixer.cpp b/services/audioflinger/FastMixer.cpp
index 7a02963..caeede9 100644
--- a/services/audioflinger/FastMixer.cpp
+++ b/services/audioflinger/FastMixer.cpp
@@ -489,6 +489,10 @@
                         timestamp.mPosition[ExtendedTimestamp::LOCATION_KERNEL];
                 mTimestamp.mTimeNs[ExtendedTimestamp::LOCATION_KERNEL] =
                         timestamp.mTimeNs[ExtendedTimestamp::LOCATION_KERNEL];
+                // We don't compensate for server - kernel time difference and
+                // only update latency if we have valid info.
+                dumpState->mLatencyMs =
+                        (double)mNativeFramesWrittenButNotPresented * 1000 / mSampleRate;
             } else {
                 // HAL reported that more frames were presented than were written
                 mNativeFramesWrittenButNotPresented = 0;