loplugin:stringconstant: handle OUString+=OUString(literal)

Change-Id: I6c82e5071038990489e85ac27758867205ba476a

vcl/generic/print/genpspgraphics.cxx

@@ -1138,7 +1138,7 @@ ImplDevFontAttributes GenPspGraphics::Info2DevFontAttributes( const psp::FastPri
     for(; it != rInfo.m_aAliases.end(); ++it )
     {
         if( bHasMapNames )
-            aDFA.maMapNames += OUString(';');
+            aDFA.maMapNames += ";";
         aDFA.maMapNames += *it;
         bHasMapNames = true;
     }

vcl/source/gdi/configsettings.cxx

@@ -70,10 +70,7 @@ void SettingsConfigItem::ImplCommit()
         SmallOUStrMap::const_iterator it;
         for( it = group->second.begin(); it != group->second.end(); ++it )
         {
-            OUString aName( aKeyName );
-            aName +=  OUString('/');
-            aName += it->first;
-            pValues[nIndex].Name    = aName;
+            pValues[nIndex].Name    = aKeyName + "/" + it->first;
             pValues[nIndex].Handle  = 0;
             pValues[nIndex].Value <<= it->second;
             pValues[nIndex].State   = PropertyState_DIRECT_VALUE;
@@ -108,10 +105,7 @@ void SettingsConfigItem::getValues()
         OUString* pTo = aSettingsKeys.getArray();
         for( int m = 0; m < aKeys.getLength(); m++ )
         {
-            OUString aName( aKeyName );
-            aName += OUString('/');
-            aName += pFrom[m];
-            pTo[m] = aName;
+            pTo[m] = aKeyName + "/" + pFrom[m];
         }
         Sequence< Any > aValues( GetProperties( aSettingsKeys ) );
         const Any* pValue = aValues.getConstArray();

vcl/unx/gtk/fpicker/SalGtkFilePicker.cxx

@@ -1906,7 +1906,7 @@ void SalGtkFilePicker::SetFilters()
             for (std::set<OUString>::const_iterator aIter = aAllFormats.begin(); aIter != aEnd; ++aIter)
             {
                 if (!sAllFilter.isEmpty())
-                    sAllFilter += OUString(';');
+                    sAllFilter += ";";
                 sAllFilter += *aIter;
             }
             sPseudoFilter = getResString(FILE_PICKER_ALLFORMATS);