aaudio: improve accuracy of timestamps

Account for latency added by the AAudio service.
Fix input timestamps.

Bug: 37080396
Test: test_timestamps.cpp input_monitor.cpp
Change-Id: I1053cd21af722bb9b9371df4e5731bf4a0a57b0b
diff --git a/services/oboeservice/AAudioServiceEndpoint.cpp b/services/oboeservice/AAudioServiceEndpoint.cpp
index 0f863fe..6c345cd 100644
--- a/services/oboeservice/AAudioServiceEndpoint.cpp
+++ b/services/oboeservice/AAudioServiceEndpoint.cpp
@@ -177,7 +177,10 @@
             configuration.getSamplesPerFrame() != mStreamInternal->getSamplesPerFrame()) {
         return false;
     }
-
     return true;
 }
 
+
+aaudio_result_t AAudioServiceEndpoint::getTimestamp(int64_t *positionFrames, int64_t *timeNanos) {
+    return mStreamInternal->getTimestamp(CLOCK_MONOTONIC, positionFrames, timeNanos);
+}