LibPDF: Clip stroke for B / B* operators

Fixes pages 17-19 on
https://www.iro.umontreal.ca/~feeley/papers/ChevalierBoisvertFeeleyECOOP15.pdf

Calling the fill handler after painting the stroke as previously doesn't
work, since we need to set up the clip before both stroke and fill, and
unset it after both. The duplication is a bit unfortunate, but also
minor.

Userland/Libraries/LibPDF/Renderer.cpp

@@ -388,22 +388,38 @@ RENDERER_HANDLER(path_fill_evenodd)
 
 RENDERER_HANDLER(path_fill_stroke_nonzero)
 {
+ begin_path_paint();
  if (state().stroke_style.has<NonnullRefPtr<Gfx::PaintStyle>>()) {
  m_anti_aliasing_painter.stroke_path(m_current_path, state().stroke_style.get<NonnullRefPtr<Gfx::PaintStyle>>(), line_width());
  } else {
  m_anti_aliasing_painter.stroke_path(m_current_path, state().stroke_style.get<Color>(), line_width());
  }
- return handle_path_fill_nonzero(args);
+ m_current_path.close_all_subpaths();
+ if (state().paint_style.has<NonnullRefPtr<Gfx::PaintStyle>>()) {
+ m_anti_aliasing_painter.fill_path(m_current_path, state().paint_style.get<NonnullRefPtr<Gfx::PaintStyle>>(), 1.0, Gfx::Painter::WindingRule::Nonzero);
+ } else {
+ m_anti_aliasing_painter.fill_path(m_current_path, state().paint_style.get<Color>(), Gfx::Painter::WindingRule::Nonzero);
+ }
+ end_path_paint();
+ return {};
 }
 
 RENDERER_HANDLER(path_fill_stroke_evenodd)
 {
+ begin_path_paint();
  if (state().stroke_style.has<NonnullRefPtr<Gfx::PaintStyle>>()) {
  m_anti_aliasing_painter.stroke_path(m_current_path, state().stroke_style.get<NonnullRefPtr<Gfx::PaintStyle>>(), line_width());
  } else {
  m_anti_aliasing_painter.stroke_path(m_current_path, state().stroke_style.get<Color>(), line_width());
  }
- return handle_path_fill_evenodd(args);
+ m_current_path.close_all_subpaths();
+ if (state().paint_style.has<NonnullRefPtr<Gfx::PaintStyle>>()) {
+ m_anti_aliasing_painter.fill_path(m_current_path, state().paint_style.get<NonnullRefPtr<Gfx::PaintStyle>>(), 1.0, Gfx::Painter::WindingRule::EvenOdd);
+ } else {
+ m_anti_aliasing_painter.fill_path(m_current_path, state().paint_style.get<Color>(), Gfx::Painter::WindingRule::EvenOdd);
+ }
+ end_path_paint();
+ return {};
 }
 
 RENDERER_HANDLER(path_close_fill_stroke_nonzero)