Merge "Include real to elapsed time offset in transition trace" into udc-dev

core/proto/android/server/windowmanagertransitiontrace.proto

@@ -44,6 +44,10 @@ message TransitionTraceProto {
   // Additional debugging info only collected and dumped when explicitly requested to trace
   repeated TransitionState transition_states = 3;
   repeated TransitionInfo transition_info = 4;
+
+  /* offset between real-time clock and elapsed time clock in nanoseconds.
+   Calculated as: 1000000 * System.currentTimeMillis() - SystemClock.elapsedRealtimeNanos() */
+  optional fixed64 real_to_elapsed_time_offset_nanos = 5;
 }
 
 message Transition {

services/core/java/com/android/server/wm/TransitionTracer.java

@@ -21,6 +21,7 @@ import static android.os.Build.IS_USER;
 import static com.android.server.wm.shell.TransitionTraceProto.MAGIC_NUMBER;
 import static com.android.server.wm.shell.TransitionTraceProto.MAGIC_NUMBER_H;
 import static com.android.server.wm.shell.TransitionTraceProto.MAGIC_NUMBER_L;
+import static com.android.server.wm.shell.TransitionTraceProto.REAL_TO_ELAPSED_TIME_OFFSET_NANOS;
 
 import android.annotation.NonNull;
 import android.annotation.Nullable;
@@ -37,6 +38,7 @@ import java.io.File;
 import java.io.IOException;
 import java.io.PrintWriter;
 import java.util.ArrayList;
+import java.util.concurrent.TimeUnit;
 
 /**
  * Helper class to collect and dump transition traces.
@@ -395,6 +397,10 @@ public class TransitionTracer {
         try {
             ProtoOutputStream proto = new ProtoOutputStream();
             proto.write(MAGIC_NUMBER, MAGIC_NUMBER_VALUE);
+            long timeOffsetNs =
+                    TimeUnit.MILLISECONDS.toNanos(System.currentTimeMillis())
+                            - SystemClock.elapsedRealtimeNanos();
+            proto.write(REAL_TO_ELAPSED_TIME_OFFSET_NANOS, timeOffsetNs);
             int pid = android.os.Process.myPid();
             LogAndPrintln.i(pw, "Writing file to " + file.getAbsolutePath()
                     + " from process " + pid);