tdf#125777 restore old RenderContext before return

Regression from commit 710f3c63af2d ("tdf#125670 just check gradient
clipping on drawing")

Change-Id: I6acf23675414983bd07639703f43aa934c0a48ed
Reviewed-on: https://gerrit.libreoffice.org/74502
Tested-by: Jenkins
Reviewed-by: Jan-Marek Glogowski <glogow@fbihome.de>
diff --git a/vcl/source/outdev/gradient.cxx b/vcl/source/outdev/gradient.cxx
index d356355..3e50a01 100644
--- a/vcl/source/outdev/gradient.cxx
+++ b/vcl/source/outdev/gradient.cxx
@@ -101,8 +101,11 @@
                if( mbInitClipRegion )
                    InitClipRegion();

                if ( mbOutputClipped )
                if (mbOutputClipped)
                {
                    Pop();
                    return;
                }

                // try to draw gradient natively
                bDrawn = mpGraphics->DrawGradient( aClixPolyPoly, aGradient );