fix center alignment

Signed-off-by: Andy Scherzinger <info@andy-scherzinger.de>

app/src/main/res/layout/controller_conversation_info.xml

@@ -54,7 +54,7 @@
         android:id="@+id/progressBar"
         android:layout_width="@dimen/item_height"
         android:layout_height="@dimen/item_height"
-        android:layout_centerInParent="true"
+        android:layout_gravity="center"
         android:layout_marginStart="@dimen/activity_horizontal_margin"
         android:layout_marginLeft="@dimen/activity_horizontal_margin"
         android:layout_marginEnd="@dimen/activity_horizontal_margin"