create appendCopy method in OUStringBuffer

so we can avoid temporary copies when appending a substring of an
OUString to the buffer. I would have preferred to call the method just
"append" but that results in ambiguous method errors when the callsite
is something like
   sal_Int32 n;
   OUStringBuffer s;
   s.append(n, 10);
I'm not sure why

Change-Id: I6b5b6641fcb5b26ce2269f89ef06e03c0b6aa76f
Reviewed-on: https://gerrit.libreoffice.org/58666
Tested-by: Jenkins
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>

1 files changed, 2 insertions, 2 deletions

diff --git a/vbahelper/source/vbahelper/vbacommandbarhelper.cxx b/vbahelper/source/vbahelper/vbacommandbarhelper.cxx
index 70c5705b5b72..058ddc2a4142 100644
--- a/vbahelper/source/vbahelper/vbacommandbarhelper.cxx
+++ b/vbahelper/source/vbahelper/vbacommandbarhelper.cxx
@@ -226,10 +226,10 @@ sal_Int32 VbaCommandBarHelper::findControlByName( const css::uno::Reference< css
         }
         else
         {
-            aBuffer.append( sLabel.copy( 0, index ) );
+            aBuffer.appendCopy( sLabel, 0, index );
             if( bMenu )
                 aBuffer.append( '&' );
-            aBuffer.append( sLabel.copy( index + 1 ) );
+            aBuffer.appendCopy( sLabel, index + 1 );
         }
         OUString sNewLabel = aBuffer.makeStringAndClear();
         SAL_INFO("vbahelper", "VbaCommandBarHelper::findControlByName, control name: " << sNewLabel);