patch 8.1.1230: a lot of code is shared between vim.exe and gvim.exe

Problem:    A lot of code is shared between vim.exe and gvim.exe.
Solution:   Optionally put the shared code in vim.dll. (Ken Takata,
            closes #4287)
diff --git a/src/proto/gui.pro b/src/proto/gui.pro
index 4004bc7..f8f80b5 100644
--- a/src/proto/gui.pro
+++ b/src/proto/gui.pro
@@ -1,5 +1,5 @@
 /* gui.c */
-void gui_start(void);
+void gui_start(char_u *arg);
 void gui_prepare(int *argc, char **argv);
 int gui_init_check(void);
 void gui_init(void);
diff --git a/src/proto/gui_w32.pro b/src/proto/gui_w32.pro
index 6756dc8..4ead92e 100644
--- a/src/proto/gui_w32.pro
+++ b/src/proto/gui_w32.pro
@@ -61,6 +61,7 @@
 char_u *gui_mch_browse(int saving, char_u *title, char_u *dflt, char_u *ext, char_u *initdir, char_u *filter);
 char_u *gui_mch_browsedir(char_u *title, char_u *initdir);
 void gui_mch_set_parent(char *title);
+char *gui_mch_do_spawn(char_u *arg);
 void gui_mch_prepare(int *argc, char **argv);
 int gui_mch_init(void);
 void gui_mch_set_shellsize(int width, int height, int min_width, int min_height, int base_width, int base_height, int direction);
diff --git a/src/proto/misc2.pro b/src/proto/misc2.pro
index 3c88efb..566c973 100644
--- a/src/proto/misc2.pro
+++ b/src/proto/misc2.pro
@@ -108,4 +108,5 @@
 int mch_parse_cmd(char_u *cmd, int use_shcf, char ***argv, int *argc);
 int build_argv_from_string(char_u *cmd, char ***argv, int *argc);
 int build_argv_from_list(list_T *l, char ***argv, int *argc);
+int write_session_file(char_u *filename);
 /* vim: set ft=c : */
diff --git a/src/proto/os_mswin.pro b/src/proto/os_mswin.pro
index 2548d00..6cc8a5d 100644
--- a/src/proto/os_mswin.pro
+++ b/src/proto/os_mswin.pro
@@ -1,5 +1,5 @@
 /* os_mswin.c */
-void mch_exit(int r);
+void mch_exit_g(int r);
 void mch_early_init(void);
 int mch_input_isatty(void);
 void mch_settitle(char_u *title, char_u *icon);
diff --git a/src/proto/os_win32.pro b/src/proto/os_win32.pro
index ca5bad6..6240288 100644
--- a/src/proto/os_win32.pro
+++ b/src/proto/os_win32.pro
@@ -1,5 +1,6 @@
 /* os_win32.c */
 HINSTANCE vimLoadLib(char *name);
+int mch_is_gui_executable(void);
 HINSTANCE find_imported_module_by_funcname(HINSTANCE hInst, const char *funcname);
 void *get_dll_import_func(HINSTANCE hInst, const char *funcname);
 int dyn_libintl_init(void);