Delete dead code function SpotShadow::makeClockwise

Delete SpotShadow::makeClockwise, which is unused and does
not link when compiler optimizations are disabled (for debugging).
SpotShadow::makeClockwise calls non-existent function
ShadowTessellator::isClockwise, which only works because the
optimizer deletes the function.

Change-Id: Ib8a014bf168782772faa1da7d75a079c1fd28ed9

libs/hwui/ShadowTessellator.h

@@ -80,8 +80,6 @@ public:
 
     static Vector2 centroid2d(const Vector2* poly, int polyLength);
 
-    static bool isClockwise(const Vector2* polygon, int len);
-
     static Vector2 calculateNormal(const Vector2& p1, const Vector2& p2);
 
     static int getExtraVertexNumber(const Vector2& vector1, const Vector2& vector2,

libs/hwui/SpotShadow.cpp

@@ -301,21 +301,6 @@ bool SpotShadow::testPointInsidePolygon(const Vector2 testPoint,
     return c;
 }
 
-/**
- * Make the polygon turn clockwise.
- *
- * @param polygon the polygon as a Vector2 array.
- * @param len the number of points of the polygon
- */
-void SpotShadow::makeClockwise(Vector2* polygon, int len) {
-    if (polygon == nullptr  || len == 0) {
-        return;
-    }
-    if (!ShadowTessellator::isClockwise(polygon, len)) {
-        reverse(polygon, len);
-    }
-}
-
 /**
  * Reverse the polygon
  *

libs/hwui/SpotShadow.h

@@ -54,7 +54,6 @@ private:
     static void quicksortX(Vector2* points, int low, int high);
 
     static bool testPointInsidePolygon(const Vector2 testPoint, const Vector2* poly, int len);
-    static void makeClockwise(Vector2* polygon, int len);
     static void reverse(Vector2* polygon, int len);
 
     static void generateTriangleStrip(bool isCasterOpaque, float shadowStrengthScale,