LibWeb: Rename painter() to recording_painter() in PaintContext

Using recording_painter() as a name is less misleading, indicating
the painter in stacking context traversal doesn't perform actual
painting commands.

Userland/Libraries/LibWeb/Painting/RadioButtonPaintable.cpp

@@ -40,7 +40,7 @@ void RadioButtonPaintable::paint(PaintContext& context, PaintPhase phase) const
     auto draw_circle = [&](auto const& rect, Color color) {
         // Note: Doing this is a bit more forgiving than draw_circle() which will round to the nearset even radius.
         // This will fudge it (which works better here).
-        context.painter().fill_rect_with_rounded_corners(rect, color, rect.width() / 2);
+        context.recording_painter().fill_rect_with_rounded_corners(rect, color, rect.width() / 2);
     };
 
     auto shrink_all = [&](auto const& rect, int amount) {