patch 8.1.2001: some source files are too big

Problem:    Some source files are too big.
Solution:   Move buffer and window related functions to evalbuffer.c and
            evalwindow.c. (Yegappan Lakshmanan, closes #4898)
diff --git a/src/proto/evalfunc.pro b/src/proto/evalfunc.pro
index e2d1467..83dfacf 100644
--- a/src/proto/evalfunc.pro
+++ b/src/proto/evalfunc.pro
@@ -5,11 +5,13 @@
 int call_internal_func(char_u *name, int argcount, typval_T *argvars, typval_T *rettv);
 int call_internal_method(char_u *name, int argcount, typval_T *argvars, typval_T *rettv, typval_T *basetv);
 linenr_T tv_get_lnum(typval_T *argvars);
+linenr_T tv_get_lnum_buf(typval_T *argvars, buf_T *buf);
 buf_T *buflist_find_by_name(char_u *name, int curtab_only);
 buf_T *tv_get_buf(typval_T *tv, int curtab_only);
 buf_T *get_buf_arg(typval_T *arg);
 win_T *get_optional_window(typval_T *argvars, int idx);
 void execute_redir_str(char_u *value, int value_len);
+void execute_common(typval_T *argvars, typval_T *rettv, int arg_off);
 void mzscheme_call_vim(char_u *name, typval_T *args, typval_T *rettv);
 float_T vim_round(float_T f);
 long do_searchpair(char_u *spat, char_u *mpat, char_u *epat, int dir, typval_T *skip, int flags, pos_T *match_pos, linenr_T lnum_stop, long time_limit);