Drop KDE5FilePicker::cancel

Base class's 'Qt5FilePicker::cancel' already does nothing
just the same way.

Change-Id: Ie125d117f27849b29f082c72e320c1021e81163e
Reviewed-on: https://gerrit.libreoffice.org/68053
Tested-by: Jenkins
Reviewed-by: Katarina Behrens <Katarina.Behrens@cib.de>

vcl/unx/kde5/KDE5FilePicker.hxx

@@ -92,9 +92,6 @@ public:
     // XInitialization
     virtual void SAL_CALL initialize(const css::uno::Sequence<css::uno::Any>& rArguments) override;
 
-    // XCancellable
-    virtual void SAL_CALL cancel() override;
-
     // XServiceInfo
     virtual OUString SAL_CALL getImplementationName() override;
     virtual sal_Bool SAL_CALL supportsService(const OUString& rServiceName) override;

vcl/unx/kde5/KDE5FilePicker2.cxx

@@ -555,12 +555,6 @@ void SAL_CALL KDE5FilePicker::initialize(const uno::Sequence<uno::Any>& args)
     setTitle(VclResId(saveDialog ? STR_FPICKER_SAVE : STR_FPICKER_OPEN));
 }
 
-// XCancellable
-void SAL_CALL KDE5FilePicker::cancel()
-{
-    // TODO
-}
-
 // XServiceInfo
 OUString SAL_CALL KDE5FilePicker::getImplementationName()
 {