SwViewShell::ImplEndAction: still paint directly when non-double-buffering

It turns out that in this case it hurts performance if we go via
invaliation-then-paint instead of direct painting when double-buffering
is not enabled.

Related commits:

- beb4aa21d61f0d66392d596be86fb57b4b167239 (SwViewShell::ImplEndAction:
  avoid direct paint, 2015-06-29) and
  c9175a1bd3249ad573ae6827bf19963a3ebe2fbc (SwViewShell::ImplEndAction:
  avoid direct PaintDesktop(), 2015-07-03) globally avoided direct paints
- 222f10e773ba51a19880be1b798990260c198147 (tdf#93096 sw: fix selection
  with keyboard outside current view, 2015-08-18) restored direct paint
  when non-double-buffering for the second commit, this one does the
  same for the first

Change-Id: Ida0c6917a8cdec74209bd64813c7876d4fa61b8a
diff --git a/sw/source/core/view/viewsh.cxx b/sw/source/core/view/viewsh.cxx
index 4f8edf7..cd4bd17 100644
--- a/sw/source/core/view/viewsh.cxx
+++ b/sw/source/core/view/viewsh.cxx
@@ -419,7 +419,10 @@ void SwViewShell::ImplEndAction( const bool bIdleEnd )

                            if ( bPaintsFromSystem )
                                PaintDesktop(*GetOut(), aRect);
                            pCurrentLayout->GetCurrShell()->InvalidateWindows(aRect.SVRect());
                            if (!isTiledRendering())
                                pCurrentLayout->Paint( *mpOut, aRect );
                            else
                                pCurrentLayout->GetCurrShell()->InvalidateWindows(aRect.SVRect());

                            // #i75172# end DrawingLayer paint
                            DLPostPaint2(true);