[Engine] Remove dead code for RoundedSuperellipse (#164163)

Remove dead code that occurred during development and I forgot to
remove.

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engine/src/flutter/impeller/geometry/round_superellipse_param.cc

@@ -164,8 +164,6 @@ RoundSuperellipseParam::Octant ComputeOctant(Point center,
       .se_n = n,
       .se_max_theta = asin(sin_thetaJ),
 
-      .ratio = ratio,
-
       .circle_start = pointJ,
       .circle_center = circle_center,
       .circle_max_angle = circle_max_angle,
@@ -318,23 +316,4 @@ bool RoundSuperellipseParam::Contains(const Point& point) const {
          CornerContains(bottom_left, point) && CornerContains(top_left, point);
 }
 
-void RoundSuperellipseParam::SuperellipseBezierArc(
-    Point* output,
-    const RoundSuperellipseParam::Octant& param) {
-  Point start = {param.se_center.x, param.edge_mid.y};
-  const Point& end = param.circle_start;
-  constexpr Point start_tangent = {1, 0};
-  Point circle_start_vector = param.circle_start - param.circle_center;
-  Point end_tangent =
-      Point{-circle_start_vector.y, circle_start_vector.x}.Normalize();
-
-  Scalar start_factor = LerpPrecomputedVariable(0, param.ratio);
-  Scalar end_factor = LerpPrecomputedVariable(1, param.ratio);
-
-  output[0] = start;
-  output[1] = start + start_tangent * start_factor * param.se_a;
-  output[2] = end + end_tangent * end_factor * param.se_a;
-  output[3] = end;
-}
-
 }  // namespace impeller

engine/src/flutter/impeller/geometry/round_superellipse_param.h

@@ -45,8 +45,6 @@ struct RoundSuperellipseParam {
     // used in the curve's parametric equation.
     Scalar se_max_theta;
 
-    Scalar ratio;
-
     // The coordinate of the top left end of the circular arc, relative to the
     // `offset` point.
     Point circle_start;
@@ -123,10 +121,6 @@ struct RoundSuperellipseParam {
   // Experiments indicate that the gap is linear with respect to the corner
   // radius on that dimension.
   static constexpr Scalar kGapFactor = 0.29289321881f;  // 1-cos(pi/4)
-
-  static void SuperellipseBezierArc(
-      Point* output,
-      const RoundSuperellipseParam::Octant& param);
 };
 
 }  // namespace impeller