loplugin:stringadd simplify some *StringBuffer operations

pulled from a larger patch which I created with a more permissive
variant of this plugin

Change-Id: I7abf1f3f09e84703b6e0e52fe9587dff691b2187
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/114875
Tested-by: Jenkins
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>

1 files changed, 2 insertions, 5 deletions

diff --git a/desktop/source/deployment/gui/dp_gui_dialog2.cxx b/desktop/source/deployment/gui/dp_gui_dialog2.cxx
index a3c33f6d639d..730854127ac2 100644
--- a/desktop/source/deployment/gui/dp_gui_dialog2.cxx
+++ b/desktop/source/deployment/gui/dp_gui_dialog2.cxx
@@ -640,11 +640,8 @@ uno::Sequence< OUString > ExtMgrDialog::raiseAddPicker()
             supportedFilters.append(filter);
             if ( ! insertion.second )
             { // already existing, append extensions:
-                OUStringBuffer buf;
-                buf.append( insertion.first->second );
-                buf.append( ';' );
-                buf.append( filter );
-                insertion.first->second = buf.makeStringAndClear();
+                insertion.first->second = insertion.first->second +
+                    ";" + filter;
             }
         }
     }