tdf#112689:Replace chained O(U)StringBuffer::append() with operator+

Change-Id: I6e80e83fcdd596f641bce9b246aa634dd0cbae09
Reviewed-on: https://gerrit.libreoffice.org/67966
Tested-by: Jenkins
Reviewed-by: Michael Stahl <Michael.Stahl@cib.de>

extensions/source/propctrlr/eformshelper.cxx

@@ -57,12 +57,10 @@ namespace pcr
 
         OUString composeModelElementUIName( const OUString& _rModelName, const OUString& _rElementName )
         {
-            OUStringBuffer aBuffer;
-            aBuffer.append( "[" );
-            aBuffer.append( _rModelName );
-            aBuffer.append( "] " );
-            aBuffer.append( _rElementName );
-            return aBuffer.makeStringAndClear();
+            OUString a = "["
+                       + _rModelName + "] "
+                       + _rElementName;
+            return a;
         }
     }