Fix DownloadService doesn't stop when the app is killed

Also fixed showing "remove notification" when download is completed.

Issue:#4469
Issue:#4488

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=203927268

library/core/src/main/java/com/google/android/exoplayer2/offline/DownloadService.java

@@ -90,6 +90,7 @@ public abstract class DownloadService extends Service {
   private DownloadManagerListener downloadManagerListener;
   private int lastStartId;
   private boolean startedInForeground;
+  private boolean taskRemoved;
 
   /**
    * Creates a DownloadService with {@link #DEFAULT_FOREGROUND_NOTIFICATION_UPDATE_INTERVAL}.
@@ -221,12 +222,17 @@ public abstract class DownloadService extends Service {
   @Override
   public int onStartCommand(Intent intent, int flags, int startId) {
     lastStartId = startId;
+    taskRemoved = false;
     String intentAction = null;
     if (intent != null) {
       intentAction = intent.getAction();
       startedInForeground |=
           intent.getBooleanExtra(KEY_FOREGROUND, false) || ACTION_RESTART.equals(intentAction);
     }
+    // intentAction is null if the service is restarted or no action is specified.
+    if (intentAction == null) {
+      intentAction = ACTION_INIT;
+    }
     logd("onStartCommand action: " + intentAction + " startId: " + startId);
     switch (intentAction) {
       case ACTION_INIT:
@@ -266,6 +272,12 @@ public abstract class DownloadService extends Service {
     return START_STICKY;
   }
 
+  @Override
+  public void onTaskRemoved(Intent rootIntent) {
+    logd("onTaskRemoved rootIntent: " + rootIntent);
+    taskRemoved = true;
+  }
+
   @Override
   public void onDestroy() {
     logd("onDestroy");
@@ -363,8 +375,13 @@ public abstract class DownloadService extends Service {
     if (startedInForeground && Util.SDK_INT >= 26) {
       foregroundNotificationUpdater.showNotificationIfNotAlready();
     }
-    boolean stopSelfResult = stopSelfResult(lastStartId);
+    if (Util.SDK_INT < 28 && taskRemoved) { // See [Internal: b/74248644].
-    logd("stopSelf(" + lastStartId + ") result: " + stopSelfResult);
+      stopSelf();
+      logd("stopSelf()");
+    } else {
+      boolean stopSelfResult = stopSelfResult(lastStartId);
+      logd("stopSelf(" + lastStartId + ") result: " + stopSelfResult);
+    }
   }
 
   private void logd(String message) {

library/ui/src/main/java/com/google/android/exoplayer2/ui/DownloadNotificationUtil.java

@@ -55,10 +55,18 @@ public final class DownloadNotificationUtil {
     int downloadTaskCount = 0;
     boolean allDownloadPercentagesUnknown = true;
     boolean haveDownloadedBytes = false;
+    boolean haveDownloadTasks = false;
+    boolean haveRemoveTasks = false;
     for (TaskState taskState : taskStates) {
-      if (taskState.action.isRemoveAction || taskState.state != TaskState.STATE_STARTED) {
+      if (taskState.state != TaskState.STATE_STARTED
+          && taskState.state != TaskState.STATE_COMPLETED) {
         continue;
       }
+      if (taskState.action.isRemoveAction) {
+        haveRemoveTasks = true;
+        continue;
+      }
+      haveDownloadTasks = true;
       if (taskState.downloadPercentage != C.PERCENTAGE_UNSET) {
         allDownloadPercentagesUnknown = false;
         totalPercentage += taskState.downloadPercentage;
@@ -67,18 +75,20 @@ public final class DownloadNotificationUtil {
       downloadTaskCount++;
     }
 
-    boolean haveDownloadTasks = downloadTaskCount > 0;
     int titleStringId =
         haveDownloadTasks
             ? R.string.exo_download_downloading
-            : (taskStates.length > 0 ? R.string.exo_download_removing : NULL_STRING_ID);
+            : (haveRemoveTasks ? R.string.exo_download_removing : NULL_STRING_ID);
     NotificationCompat.Builder notificationBuilder =
         newNotificationBuilder(
             context, smallIcon, channelId, contentIntent, message, titleStringId);
 
-    int progress = haveDownloadTasks ? (int) (totalPercentage / downloadTaskCount) : 0;
+    int progress = 0;
-    boolean indeterminate =
+    boolean indeterminate = true;
-        !haveDownloadTasks || (allDownloadPercentagesUnknown && haveDownloadedBytes);
+    if (haveDownloadTasks) {
+      progress = (int) (totalPercentage / downloadTaskCount);
+      indeterminate = allDownloadPercentagesUnknown && haveDownloadedBytes;
+    }
     notificationBuilder.setProgress(/* max= */ 100, progress, indeterminate);
     notificationBuilder.setOngoing(true);
     notificationBuilder.setShowWhen(false);