tdf#135121 don't fill the rectangle in the transparent case at all

leave the area untouched

Change-Id: Icf195d383271b92f6523f8c6b6bc3b87fcae00be
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/99955
Tested-by: Jenkins
Reviewed-by: Caolán McNamara <caolanm@redhat.com>
diff --git a/svx/source/tbxctrls/tbxcolorupdate.cxx b/svx/source/tbxctrls/tbxcolorupdate.cxx
index 7c2b3bd..9d400ff 100644
--- a/svx/source/tbxctrls/tbxcolorupdate.cxx
+++ b/svx/source/tbxctrls/tbxcolorupdate.cxx
@@ -205,7 +205,7 @@ namespace svx

        if (bIsTransparent)
        {
            pVirDev->SetFillColor(Color(255, 0, 0, 0));
            pVirDev->SetFillColor();
        }
        else
        {