LibWeb: Extract CanvasDrawPath class from CRC2D

Again, this is an entirely virtual class since the methods involve
direct access to the Painter. Though, maybe I could just expose the
Painter...

Userland/Libraries/LibWeb/Forward.h

@@ -648,6 +648,7 @@ class XMLHttpRequestPrototype;
 class XMLHttpRequestWrapper;
 class XMLSerializerWrapper;
 enum class CanPlayTypeResult;
+enum class CanvasFillRule;
 enum class EndingType;
 enum class DOMParserSupportedType;
 enum class ResizeObserverBoxOptions;