Properly handle transient states

app/src/main/java/eu/faircode/email/SimpleTask.java

@@ -118,6 +118,8 @@ public abstract class SimpleTask<T> implements LifecycleObserver {
         this.stored = null;
         owner.getLifecycle().addObserver(this);
 
+        onInit(args);
+
         // Run in background thread
         executor.submit(new Runnable() {
             @Override
@@ -162,6 +164,9 @@ public abstract class SimpleTask<T> implements LifecycleObserver {
         }
     }
 
+    protected void onInit(Bundle args) {
+    }
+
     protected T onLoad(Context context, Bundle args) throws Throwable {
         // Be careful not to access members in outer scopes
         return null;