Don't use Context#startForegroundService() because we may get killed

If the foreground service doesn't have anything to do and terminates quickly, the system will kill us, even though the service had called startForeground(). To prevent this, we don't promise that our service will be a foreground service. We can still be a foreground service, but escape the punishment if we are too quick.

app/src/main/java/com/stevesoltys/seedvault/restore/AppDataRestoreManager.kt

@@ -123,7 +123,8 @@ internal class AppDataRestoreManager(
                 RestoreBackupResult(context.getString(R.string.restore_set_error))
             )
         } else {
-            context.startForegroundService(foregroundServiceIntent)
+            // don't use startForeground(), because we may stop it sooner than the system likes
+            context.startService(foregroundServiceIntent)
         }
     }
 

app/src/main/java/com/stevesoltys/seedvault/restore/install/ApkRestore.kt

@@ -90,7 +90,8 @@ internal class ApkRestore(
         val i = Intent(context, RestoreService::class.java)
         val autoRestore = backupStateManager.isAutoRestoreEnabled
         try {
-            context.startForegroundService(i)
+            // don't use startForeground(), because we may stop it sooner than the system likes
+            context.startService(i)
             // disable auto-restore before installing apps, if it was enabled before
             if (autoRestore) backupManager.setAutoRestore(false)
             reInstallApps(backup, packages.asIterable().reversed())