Add a rolling log of external vibrations

Bug: 133200481
Test: Dump vibrator service after some audio-coupled vibrations
Change-Id: I3c5d8e3f6ce6828282780ece9d5977138b154040

services/core/java/com/android/server/VibratorService.java

@@ -116,6 +116,7 @@ public class VibratorService extends IVibratorService.Stub
     private final LinkedList<VibrationInfo> mPreviousRingVibrations;
     private final LinkedList<VibrationInfo> mPreviousNotificationVibrations;
     private final LinkedList<VibrationInfo> mPreviousAlarmVibrations;
+    private final LinkedList<ExternalVibration> mPreviousExternalVibrations;
     private final LinkedList<VibrationInfo> mPreviousVibrations;
     private final int mPreviousVibrationsLimit;
     private final boolean mAllowPriorityVibrationsInLowPowerMode;
@@ -368,6 +369,7 @@ public class VibratorService extends IVibratorService.Stub
         mPreviousNotificationVibrations = new LinkedList<>();
         mPreviousAlarmVibrations = new LinkedList<>();
         mPreviousVibrations = new LinkedList<>();
+        mPreviousExternalVibrations = new LinkedList<>();
 
         IntentFilter filter = new IntentFilter();
         filter.addAction(Intent.ACTION_SCREEN_OFF);
@@ -1418,6 +1420,12 @@ public class VibratorService extends IVibratorService.Stub
                 pw.print("    ");
                 pw.println(info.toString());
             }
+
+            pw.println("  Previous external vibrations:");
+            for (ExternalVibration vib : mPreviousExternalVibrations) {
+                pw.print("    ");
+                pw.println(vib.toString());
+            }
         }
     }
 
@@ -1462,6 +1470,10 @@ public class VibratorService extends IVibratorService.Stub
                     // Note that this doesn't support multiple concurrent external controls, as we
                     // would need to mute the old one still if it came from a different controller.
                     mCurrentExternalVibration = vib;
+                    if (mPreviousExternalVibrations.size() > mPreviousVibrationsLimit) {
+                        mPreviousExternalVibrations.removeFirst();
+                    }
+                    mPreviousExternalVibrations.addLast(vib);
                     if (DEBUG) {
                         Slog.e(TAG, "Playing external vibration: " + vib);
                     }