Move exc state to generator. Fixes bpo-25612 (#1773)
Move exception state information from frame objects to coroutine (generator/thread) object where it belongs.
diff --git a/Include/pyerrors.h b/Include/pyerrors.h
index fcaba85..9418201 100644
--- a/Include/pyerrors.h
+++ b/Include/pyerrors.h
@@ -78,6 +78,7 @@
PyAPI_FUNC(void) PyErr_SetObject(PyObject *, PyObject *);
#ifndef Py_LIMITED_API
PyAPI_FUNC(void) _PyErr_SetKeyError(PyObject *);
+_PyErr_StackItem *_PyErr_GetTopmostException(PyThreadState *tstate);
#endif
PyAPI_FUNC(void) PyErr_SetString(
PyObject *exception,