use the same shade of grey as Online UI uses

Change-Id: Idb6dc80f4943323f80bc6851bc184798627722ef
Reviewed-on: https://gerrit.libreoffice.org/48056Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Andras Timar <andras.timar@collabora.com>

vcl/headless/svpframe.cxx

@@ -409,7 +409,7 @@ void SvpSalFrame::UpdateSettings( AllSettings& rSettings )
 {
     StyleSettings aStyleSettings = rSettings.GetStyleSettings();
 
-    Color aBackgroundColor( 0xec, 0xec, 0xec );
+    Color aBackgroundColor( 0xef, 0xef, 0xef );
     aStyleSettings.BatchSetBackgrounds( aBackgroundColor, false );
     aStyleSettings.SetMenuColor( aBackgroundColor );
     aStyleSettings.SetMenuBarColor( aBackgroundColor );