Re: remaining sql/json patches

hi.
minor issues.

In transformJsonFuncExpr(ParseState *pstate, JsonFuncExpr *func)
func.behavior->on_empty->location and
func.behavior->on_error->location are correct.
but in ExecInitJsonExpr, jsestate->jsexpr->on_empty->location is -1,
jsestate->jsexpr->on_error->location is -1.
Maybe we can preserve these on_empty, on_error token locations in
transformJsonBehavior.

some enum declaration, ending element need an extra comma?

+ /*
+ * ExecEvalJsonExprPath() will set this to the address of the step to
+ * use to coerce the result of JsonPath* evaluation to the RETURNING
+ * type.  Also see the description of possible step addresses this
+ * could be set to in the definition of JsonExprState.ZZ
+ */

"ZZ", typo?