LibWeb: Support transforms, stroking, gradients, etc for SVG <text>

This makes use of the new Gfx::Path::text() to handle SVG text elements,
with this text is just a regular path, and can be manipulated like any
other graphics element.

This removes the SVGTextPaintable and makes both <text> and geometry
elements use a new (shared) SVGPathPaintable. This is identical to the
old SVGGeometryPaintable. This simplifies painting as once something is
resolved to a Gfx::Path, the painting logic is the same.

Userland/Libraries/LibWeb/Painting/SVGPathPaintable.h

@@ -0,0 +1,39 @@
+/*
+ * Copyright (c) 2022, Andreas Kling <kling@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+#include <LibWeb/Layout/SVGGraphicsBox.h>
+#include <LibWeb/Painting/SVGGraphicsPaintable.h>
+
+namespace Web::Painting {
+
+class SVGPathPaintable final : public SVGGraphicsPaintable {
+    JS_CELL(SVGPathPaintable, SVGGraphicsPaintable);
+
+public:
+    static JS::NonnullGCPtr<SVGPathPaintable> create(Layout::SVGGraphicsBox const&);
+
+    virtual Optional<HitTestResult> hit_test(CSSPixelPoint, HitTestType) const override;
+
+    virtual void paint(PaintContext&, PaintPhase) const override;
+
+    Layout::SVGGraphicsBox const& layout_box() const;
+
+    void set_computed_path(Gfx::Path path)
+    {
+        m_computed_path = move(path);
+    }
+
+    Optional<Gfx::Path> const& computed_path() const { return m_computed_path; }
+
+protected:
+    SVGPathPaintable(Layout::SVGGraphicsBox const&);
+
+    Optional<Gfx::Path> m_computed_path = {};
+};
+
+}