[metrics] implement callbacks for InstalledIncrementalPackage pulled atom

BUG: 187872906
Test: 1. install 3 incremental apps; 2. run `statsd_testdrive 10114` and
wait to finish; 3. observe that the result contains 3 atoms.

gauge_metrics {
  data {
    bucket_info {
      atom {
        installed_incremental_package {
          uids: 10306
        }
      }
      atom {
        installed_incremental_package {
          uids: 10307
        }
      }
      atom {
        installed_incremental_package {
          uids: 10308
        }
      }
      elapsed_timestamp_nanos: 561691558765
      elapsed_timestamp_nanos: 561691558765
      elapsed_timestamp_nanos: 561691558765
      bucket_num: 9
    }
  }
}
time_base_elapsed_nano_seconds: 14974700031
bucket_size_nano_seconds: 60000000000
is_active: true

Change-Id: I4f1d315818af5096f4d4341de063f6a162ebaf26

services/core/java/com/android/server/stats/pull/StatsPullAtomService.java

@@ -126,6 +126,7 @@ import android.os.Trace;
 import android.os.UserHandle;
 import android.os.UserManager;
 import android.os.connectivity.WifiActivityEnergyInfo;
+import android.os.incremental.IncrementalManager;
 import android.os.storage.DiskInfo;
 import android.os.storage.StorageManager;
 import android.os.storage.VolumeInfo;
@@ -426,6 +427,7 @@ public class StatsPullAtomService extends SystemService {
     private final Object mHealthHalLock = new Object();
     private final Object mAttributedAppOpsLock = new Object();
     private final Object mSettingsStatsLock = new Object();
+    private final Object mInstalledIncrementalPackagesLock = new Object();
 
     public StatsPullAtomService(Context context) {
         super(context);
@@ -695,6 +697,10 @@ public class StatsPullAtomService extends SystemService {
                         synchronized (mSettingsStatsLock) {
                             return pullSettingsStatsLocked(atomTag, data);
                         }
+                    case FrameworkStatsLog.INSTALLED_INCREMENTAL_PACKAGE:
+                        synchronized (mInstalledIncrementalPackagesLock) {
+                            return pullInstalledIncrementalPackagesLocked(atomTag, data);
+                        }
                     default:
                         throw new UnsupportedOperationException("Unknown tagId=" + atomTag);
                 }
@@ -877,6 +883,7 @@ public class StatsPullAtomService extends SystemService {
         registerBatteryVoltage();
         registerBatteryCycleCount();
         registerSettingsStats();
+        registerInstalledIncrementalPackages();
     }
 
     private void initAndRegisterNetworkStatsPullers() {
@@ -3949,6 +3956,31 @@ public class StatsPullAtomService extends SystemService {
         return StatsManager.PULL_SUCCESS;
     }
 
+    private void registerInstalledIncrementalPackages() {
+        int tagId = FrameworkStatsLog.INSTALLED_INCREMENTAL_PACKAGE;
+        mStatsManager.setPullAtomCallback(
+                tagId,
+                null, // use default PullAtomMetadata values
+                DIRECT_EXECUTOR,
+                mStatsCallbackImpl
+        );
+    }
+
+    int pullInstalledIncrementalPackagesLocked(int atomTag, List<StatsEvent> pulledData) {
+        final PackageManager pm = mContext.getPackageManager();
+        if (!pm.hasSystemFeature(PackageManager.FEATURE_INCREMENTAL_DELIVERY)) {
+            // Incremental is not enabled on this device. The result list will be empty.
+            return StatsManager.PULL_SUCCESS;
+        }
+        List<PackageInfo> installedPackages = pm.getInstalledPackages(0);
+        for (PackageInfo pi : installedPackages) {
+            if (IncrementalManager.isIncrementalPath(pi.applicationInfo.getBaseCodePath())) {
+                pulledData.add(FrameworkStatsLog.buildStatsEvent(atomTag, pi.applicationInfo.uid));
+            }
+        }
+        return StatsManager.PULL_SUCCESS;
+    }
+
     // Thermal event received from vendor thermal management subsystem
     private static final class ThermalEventListener extends IThermalEventListener.Stub {
         @Override