LibGfx: Stop passing color stop spans by const reference

No idea why I did this, possibly because these were once vectors?
Anyway, the const reference is pointless here.

Userland/Libraries/LibGfx/GradientPainting.cpp

@@ -165,7 +165,7 @@ private:
     TransformFunction m_transform_function;
 };
 
-static auto create_linear_gradient(IntRect const& physical_rect, Span<ColorStop const> const& color_stops, float angle, Optional<float> repeat_length)
+static auto create_linear_gradient(IntRect const& physical_rect, Span<ColorStop const> color_stops, float angle, Optional<float> repeat_length)
 {
     float normalized_angle = normalized_gradient_angle_radians(angle);
     float sin_angle, cos_angle;
@@ -188,7 +188,7 @@ static auto create_linear_gradient(IntRect const& physical_rect, Span<ColorStop
     };
 }
 
-static auto create_conic_gradient(Span<ColorStop const> const& color_stops, FloatPoint center_point, float start_angle, Optional<float> repeat_length, UsePremultipliedAlpha use_premultiplied_alpha = UsePremultipliedAlpha::Yes)
+static auto create_conic_gradient(Span<ColorStop const> color_stops, FloatPoint center_point, float start_angle, Optional<float> repeat_length, UsePremultipliedAlpha use_premultiplied_alpha = UsePremultipliedAlpha::Yes)
 {
     // FIXME: Do we need/want sub-degree accuracy for the gradient line?
     GradientLine gradient_line(360, color_stops, repeat_length, use_premultiplied_alpha);
@@ -213,7 +213,7 @@ static auto create_conic_gradient(Span<ColorStop const> const& color_stops, Floa
     };
 }
 
-static auto create_radial_gradient(IntRect const& physical_rect, Span<ColorStop const> const& color_stops, IntPoint center, IntSize size, Optional<float> repeat_length)
+static auto create_radial_gradient(IntRect const& physical_rect, Span<ColorStop const> color_stops, IntPoint center, IntSize size, Optional<float> repeat_length)
 {
     // A conservative guesstimate on how many colors we need to generate:
     auto max_dimension = max(physical_rect.width(), physical_rect.height());
@@ -232,7 +232,7 @@ static auto create_radial_gradient(IntRect const& physical_rect, Span<ColorStop
     };
 }
 
-void Painter::fill_rect_with_linear_gradient(IntRect const& rect, Span<ColorStop const> const& color_stops, float angle, Optional<float> repeat_length)
+void Painter::fill_rect_with_linear_gradient(IntRect const& rect, Span<ColorStop const> color_stops, float angle, Optional<float> repeat_length)
 {
     auto a_rect = to_physical(rect);
     if (a_rect.intersected(clip_rect() * scale()).is_empty())
@@ -246,7 +246,7 @@ static FloatPoint pixel_center(IntPoint point)
     return point.to_type<float>().translated(0.5f, 0.5f);
 }
 
-void Painter::fill_rect_with_conic_gradient(IntRect const& rect, Span<ColorStop const> const& color_stops, IntPoint center, float start_angle, Optional<float> repeat_length)
+void Painter::fill_rect_with_conic_gradient(IntRect const& rect, Span<ColorStop const> color_stops, IntPoint center, float start_angle, Optional<float> repeat_length)
 {
     auto a_rect = to_physical(rect);
     if (a_rect.intersected(clip_rect() * scale()).is_empty())
@@ -257,7 +257,7 @@ void Painter::fill_rect_with_conic_gradient(IntRect const& rect, Span<ColorStop
     conic_gradient.paint(*this, a_rect);
 }
 
-void Painter::fill_rect_with_radial_gradient(IntRect const& rect, Span<ColorStop const> const& color_stops, IntPoint center, IntSize size, Optional<float> repeat_length)
+void Painter::fill_rect_with_radial_gradient(IntRect const& rect, Span<ColorStop const> color_stops, IntPoint center, IntSize size, Optional<float> repeat_length)
 {
     auto a_rect = to_physical(rect);
     if (a_rect.intersected(clip_rect() * scale()).is_empty())

Userland/Libraries/LibGfx/Painter.h

@@ -53,9 +53,9 @@ public:
     void fill_rect_with_checkerboard(IntRect const&, IntSize, Color color_dark, Color color_light);
     void fill_rect_with_gradient(Orientation, IntRect const&, Color gradient_start, Color gradient_end);
     void fill_rect_with_gradient(IntRect const&, Color gradient_start, Color gradient_end);
-    void fill_rect_with_linear_gradient(IntRect const&, Span<ColorStop const> const&, float angle, Optional<float> repeat_length = {});
-    void fill_rect_with_conic_gradient(IntRect const&, Span<ColorStop const> const&, IntPoint center, float start_angle, Optional<float> repeat_length = {});
-    void fill_rect_with_radial_gradient(IntRect const&, Span<ColorStop const> const&, IntPoint center, IntSize size, Optional<float> repeat_length = {});
+    void fill_rect_with_linear_gradient(IntRect const&, Span<ColorStop const>, float angle, Optional<float> repeat_length = {});
+    void fill_rect_with_conic_gradient(IntRect const&, Span<ColorStop const>, IntPoint center, float start_angle, Optional<float> repeat_length = {});
+    void fill_rect_with_radial_gradient(IntRect const&, Span<ColorStop const>, IntPoint center, IntSize size, Optional<float> repeat_length = {});
     void fill_rect_with_rounded_corners(IntRect const&, Color, int radius);
     void fill_rect_with_rounded_corners(IntRect const&, Color, int top_left_radius, int top_right_radius, int bottom_right_radius, int bottom_left_radius);
     void fill_ellipse(IntRect const&, Color);