Fix base handler for advanced partitioning details

The previous fix of the 'page tab' disappearing in partitioning
details (commit 9483079) was incomplete and when the situation
to be sanitized by it happened, it couldn't actually get the
visible (active) page tab node.

anabot/runtime/installation/hub/partitioning/advanced/details.py

@@ -44,6 +44,7 @@ def base_handler(element, app_node, local_node):
     for child in element.xpathEval("./*"):
         handle_step(child, app_node, local_node)
         if not details_node.visible:
+            details_node = getnode(local_node, "page tab list")
             details_node = getnodes(details_node, "page tab", sensitive=None)[0]
     return True