jsdialogs: fix nested containters lookup

Do not break the loop early if not found a widget.
We need to go up sometimes. Fixes regression from
commit	13af671fda1317175a93fd747e5455ce897ed167
jsdialog: share code for widget registry

Signed-off-by: Szymon Kłos <szymon.klos@collabora.com>
Change-Id: I5516c0708452e95b2b6067e3a1fb99582b47dcf7
(cherry picked from commit 90f836f5ef250c586fe9d58637ae15dee305edb7)
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/182537
Tested-by: Jenkins

vcl/jsdialog/jsdialogbuilder.cxx

@@ -519,11 +519,9 @@ std::unique_ptr<weld::Container> JSInstanceBuilder::weld_container(const OUStrin
         // use parent builder to send update - avoid multiple calls from many builders
         vcl::Window* pParent = pContainer->GetParent();
         OUString sId = OUString::number(m_nWindowId);
-        while (pParent)
+        auto aWidgetMap = Widgets().Find(sId);
+        while (pParent && aWidgetMap && !aWidgetMap->Find(pParent->get_id()))
         {
-            auto aWidgetMap = Widgets().Find(sId);
-            if (!aWidgetMap || !aWidgetMap->Find(pParent->get_id()))
-                break;
             pParent = pParent->GetParent();
         }