master 5795051: Add ability to bring only the selected frame to the front (bug#48865)

[Alan Third]

branch: master
commit 57950515ecb3609bc252ecd0d33c802e04bbad64
Author: Matt Beshara <m@mfa.pw>
Commit: Alan Third <alan@idiocy.org>

    Add ability to bring only the selected frame to the front (bug#48865)
    
    Causes ‘ns-hide-emacs’ to layer the selected frame in front of every other
    application’s windows, and give that frame keyboard focus, when called with
    'activate-front.
    
    * src/nsfns.m (Fns_hide_emacs): Allow activating only selected frame.
---
 src/nsfns.m | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/src/nsfns.m b/src/nsfns.m
index 98801d8..454a6fd 100644
--- a/src/nsfns.m
+++ b/src/nsfns.m
@@ -1953,8 +1953,11 @@ DEFUN ("ns-hide-emacs", Fns_hide_emacs, Sns_hide_emacs,
        doc: /* If ON is non-nil, the entire Emacs application is hidden.
 Otherwise if Emacs is hidden, it is unhidden.
 If ON is equal to `activate', Emacs is unhidden and becomes
-the active application.  */)
-     (Lisp_Object on)
+the active application.
+If ON is equal to `activate-front', Emacs is unhidden and
+becomes the active application, but only the selected frame
+is layered in front of the windows of other applications.  */)
+  (Lisp_Object on)
 {
   check_window_system (NULL);
   if (EQ (on, intern ("activate")))
@@ -1962,6 +1965,12 @@ the active application.  */)
       [NSApp unhide: NSApp];
       [NSApp activateIgnoringOtherApps: YES];
     }
+  else if (EQ (on, intern ("activate-front")))
+    {
+      [NSApp unhide: NSApp];
+      [[NSRunningApplication currentApplication]
+        activateWithOptions: NSApplicationActivateIgnoringOtherApps];
+    }
   else if (NILP (on))
     [NSApp unhide: NSApp];
   else