WASM: add required PyObject *_null parameter to remaining functions m…

…arked with METH_NOARGS in math.c and color.c (#2482)

that was good hunting !

src_c/color.c

@@ -93,7 +93,7 @@ _color_set_length(pgColorObject *, PyObject *);
 static PyObject *
 _color_lerp(pgColorObject *, PyObject *, PyObject *);
 static PyObject *
-_color_grayscale(pgColorObject *);
+_color_grayscale(pgColorObject *, PyObject *);
 static PyObject *
 _premul_alpha(pgColorObject *, PyObject *);
 static PyObject *
@@ -760,7 +760,7 @@ _color_correct_gamma(pgColorObject *color, PyObject *args)
  * color.grayscale()
  */
 static PyObject *
-_color_grayscale(pgColorObject *self)
+_color_grayscale(pgColorObject *self, PyObject *_null)
 {
     // RGBA to GRAY formula used by OpenCV
     Uint8 grayscale_pixel =

src_c/math.c

@@ -325,7 +325,7 @@ vectoriter_dealloc(vectoriter *it);
 static PyObject *
 vectoriter_next(vectoriter *it);
 static PyObject *
-vectoriter_len(vectoriter *it);
+vectoriter_len(vectoriter *it, PyObject *_null);
 static PyObject *
 vector_iter(PyObject *vec);
 
@@ -3514,7 +3514,7 @@ vectoriter_next(vectoriter *it)
 }
 
 static PyObject *
-vectoriter_len(vectoriter *it)
+vectoriter_len(vectoriter *it, PyObject *_null)
 {
     Py_ssize_t len = 0;
     if (it && it->vec) {