ShellClients: Don't declare centered windows as shell windows (#2709)

Author: leolost2605

src/Dialogs/InhibitShortcutsDialog.vala

@@ -36,7 +36,7 @@ public class Gala.InhibitShortcutsDialog : AccessDialog, Meta.InhibitShortcutsDi
         }
 
         if (app.id == "io.elementary.settings.desktop" || // Naive check to always allow inhibiting by our settings app. This is needed for setting custom shortcuts
-            ShellClientsManager.get_instance ().is_positioned_window (window) // Certain windows (e.g. centered ones) may want to disable move via super + drag
+            ShellClientsManager.get_instance ().is_shell_window (window) // Certain windows (e.g. centered ones) may want to disable move via super + drag
         ) {
             on_response (0);
             return;

src/ShellClients/ShellClientsManager.vala

@@ -233,7 +233,7 @@ public class Gala.ShellClientsManager : Object, GestureTarget {
         panel_windows[window].request_visible_in_multitasking_view ();
     }
 
-    public void make_centered (Meta.Window window) requires (!is_itself_positioned (window)) {
+    public void make_centered (Meta.Window window) requires (!is_itself_shell_window (window)) {
         positioned_windows[window] = new ExtendedBehaviorWindow (window);
 
         // connect_after so we make sure that any queued move is unqueued
@@ -254,14 +254,26 @@ public class Gala.ShellClientsManager : Object, GestureTarget {
         }
     }
 
-    public bool is_itself_positioned (Meta.Window window) {
-        return (window in positioned_windows) || (window in panel_windows) || NotificationStack.is_notification (window);
+    public bool is_itself_shell_window (Meta.Window window) {
+        return (
+            (window in positioned_windows && positioned_windows[window].modal) ||
+            (window in panel_windows) ||
+            NotificationStack.is_notification (window)
+        );
     }
 
-    public bool is_positioned_window (Meta.Window window) {
-        bool positioned = is_itself_positioned (window);
+    /**
+     * Whether the given window is a shell window. A shell window is a window that's
+     * part of the desktop shell itself and should be completely ignored by other components.
+     * It is entirely managed by Gala, always above everything else, and manages hiding
+     * in e.g. multitasking view itself. This also applies to transient windows of shell windows.
+     * Note that even if `false` is returned the window might still be in part managed by gala
+     * e.g. for centered windows.
+     */
+    public bool is_shell_window (Meta.Window window) {
+        bool positioned = is_itself_shell_window (window);
         window.foreach_ancestor ((ancestor) => {
-            if (is_itself_positioned (ancestor)) {
+            if (is_itself_shell_window (ancestor)) {
                 positioned = true;
             }
 

src/ShellClients/ShellWindow.vala

@@ -85,7 +85,7 @@ public abstract class Gala.ShellWindow : PositionedWindow, GestureTarget {
 
         unowned var manager = ShellClientsManager.get_instance ();
         window.foreach_transient ((transient) => {
-            if (manager.is_itself_positioned (transient)) {
+            if (manager.is_itself_shell_window (transient)) {
                 return true;
             }
 

src/Widgets/MultitaskingView/StaticWindowContainer.vala

@@ -71,7 +71,7 @@ public class Gala.StaticWindowContainer : ActorTarget {
     }
 
     private void check_window_changed (Meta.Window window) {
-        var is_static = is_static (window) && !ShellClientsManager.get_instance ().is_positioned_window (window);
+        var is_static = is_static (window) && !ShellClientsManager.get_instance ().is_shell_window (window);
 
         Clutter.Actor? clone = null;
         for (var child = get_first_child (); child != null; child = child.get_next_sibling ()) {

src/WindowManager.vala

@@ -43,7 +43,7 @@ namespace Gala {
 
         /**
          * The group that contains all WindowActors that make shell elements, that is all windows reported as
-         * ShellClientsManager.is_positioned_window.
+         * ShellClientsManager.is_shell_window.
          * It will (eventually) never be hidden by other components and is always on top of everything. Therefore elements are
          * responsible themselves for hiding depending on the state we are currently in (e.g. normal desktop, open multitasking view, fullscreen, etc.).
          */
@@ -714,7 +714,7 @@ namespace Gala {
             unowned var display = get_display ();
 
             if (!is_modal () || modal_stack.peek_head ().grab != null || display.focus_window == null ||
-                ShellClientsManager.get_instance ().is_positioned_window (display.focus_window)
+                ShellClientsManager.get_instance ().is_shell_window (display.focus_window)
             ) {
                 return;
             }
@@ -1032,7 +1032,7 @@ namespace Gala {
                 return;
             }
 
-            if (ShellClientsManager.get_instance ().is_positioned_window (window)) {
+            if (ShellClientsManager.get_instance ().is_shell_window (window)) {
                 InternalUtils.clutter_actor_reparent (actor, shell_group);
             }