Resolves: tdf#129119 no SfxViewFrame in startcenter

Change-Id: I16d8207314146df3dd7f5b11182650066cc97fde
Reviewed-on: https://gerrit.libreoffice.org/84148
Tested-by: Jenkins
Reviewed-by: Caolán McNamara <caolanm@redhat.com>
Tested-by: Caolán McNamara <caolanm@redhat.com>
diff --git a/cui/source/customize/CustomNotebookbarGenerator.cxx b/cui/source/customize/CustomNotebookbarGenerator.cxx
index 8c135b9..374b145 100644
--- a/cui/source/customize/CustomNotebookbarGenerator.cxx
+++ b/cui/source/customize/CustomNotebookbarGenerator.cxx
@@ -215,10 +215,13 @@ void CustomNotebookbarGenerator::modifyCustomizedUIFile(const Sequence<OUString>
void CustomNotebookbarGenerator::getFileNameAndAppName(OUString& sAppName,
                                                       OUString& sNotebookbarUIFileName)
{
    SfxViewFrame* pFrame = SfxViewFrame::Current();
    if (!pFrame)
        return;

    const auto xContext = comphelper::getProcessComponentContext();
    utl::OConfigurationTreeRoot aRoot(xContext, "org.openoffice.Office.UI.ToolbarMode/", false);
    const Reference<frame::XFrame>& xFrame
        = SfxViewFrame::Current()->GetFrame().GetFrameInterface();
    const Reference<frame::XFrame>& xFrame = pFrame->GetFrame().GetFrameInterface();
    const Reference<frame::XModuleManager> xModuleManager = frame::ModuleManager::create(xContext);

    vcl::EnumContext::Application eApp