move PyTruffle_Unicode_FromFormat declaration to header

Author: timfel

graalpython/com.oracle.graal.python.cext/src/capi.h

@@ -310,6 +310,9 @@ extern PyObject* wrapped_null;
 /* DICT */
 void* PyTruffle_Tuple_GetItem(void* jtuple, Py_ssize_t position);
 
+/* STR */
+PyObject* PyTruffle_Unicode_FromFormat(const char*, va_list, void**, int);
+
 /* BYTES, BYTEARRAY */
 int bytes_buffer_getbuffer(PyBytesObject *self, Py_buffer *view, int flags);
 int bytearray_getbuffer(PyByteArrayObject *obj, Py_buffer *view, int flags);

graalpython/com.oracle.graal.python.cext/src/errors.c

@@ -159,9 +159,6 @@ int PyErr_ExceptionMatches(PyObject *exc) {
     return PyErr_GivenExceptionMatches(PyErr_Occurred(), exc);
 }
 
-// defined without header in unicodeobject.c
-extern PyObject* PyTruffle_Unicode_FromFormat(const char*, va_list, void**, int);
-
 PyObject* PyErr_Format(PyObject* exception, const char* fmt, ...) {
     CallWithPolyglotArgs(PyObject* formatted_msg, fmt, 2, PyTruffle_Unicode_FromFormat, fmt);
     UPCALL_CEXT_VOID(_jls_PyErr_CreateAndSetException, native_to_java(exception), native_to_java(formatted_msg));