BaseTask: move register/unregister to onPre/PostExecute

app/src/androidTest/java/org/isoron/uhabits/unit/tasks/ImportDataTaskTest.java

@@ -34,8 +34,6 @@ import org.junit.runner.RunWith;
 import java.io.File;
 import java.io.IOException;
 import java.io.InputStream;
-import java.util.concurrent.CountDownLatch;
-import java.util.concurrent.TimeUnit;
 
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.equalTo;

app/src/main/java/org/isoron/uhabits/loaders/HabitListLoader.java

@@ -164,6 +164,8 @@ public class HabitListLoader
                 currentFetchTask = null;
 
                 if(listener != null) listener.onLoadFinished();
+
+                super.onPostExecute(null);
             }
 
         };
@@ -194,6 +196,8 @@ public class HabitListLoader
             {
                 if(listener != null)
                     listener.onLoadFinished();
+
+                super.onPostExecute(null);
             }
         }.execute();
     }

app/src/main/java/org/isoron/uhabits/tasks/BaseTask.java

@@ -27,27 +27,29 @@ public abstract class BaseTask extends AsyncTask<Void, Integer, Void>
 {
     private static int activeTaskCount;
 
+    @Override
+    protected void onPreExecute()
+    {
+        super.onPreExecute();
+        activeTaskCount++;
+    }
+
+    @Override
+    protected void onPostExecute(Void aVoid)
+    {
+        activeTaskCount--;
+        super.onPostExecute(null);
+    }
+
     @Override
     protected final Void doInBackground(Void... params)
     {
-        register();
         doInBackground();
-        unregister();
         return null;
     }
 
     protected abstract void doInBackground();
 
-    protected void register()
-    {
-        activeTaskCount++;
-    }
-
-    protected void unregister()
-    {
-        activeTaskCount--;
-    }
-
     public static void waitForTasks(long timeout)
             throws TimeoutException, InterruptedException
     {