LibGfx+LibWeb: Turn Gfx::Filter into a SkImageFilter wrapper

Author: https://github.com/ananas-dev
Commit: 0fcb574041
Pull-request: https://github.com/LadybirdBrowser/ladybird/pull/4692
Reviewed-by: https://github.com/kalenikaliaksandr ✅
Reviewed-by: https://github.com/konradekk

Libraries/LibWeb/HTML/Canvas/CanvasState.h

@@ -87,8 +87,8 @@ public:
         float shadow_offset_y { 0.0f };
         float shadow_blur { 0.0f };
         Gfx::Color shadow_color { Gfx::Color::Transparent };
-        Vector<Gfx::Filter> filters;
-        Optional<String> filters_string;
+        Optional<Gfx::Filter> filter;
+        Optional<String> filter_string;
         float line_width { 1 };
         Bindings::CanvasLineCap line_cap { Bindings::CanvasLineCap::Butt };
         Bindings::CanvasLineJoin line_join { Bindings::CanvasLineJoin::Miter };