From 23c3f3fdeae608de422472802ac42261ff8f55fe Mon Sep 17 00:00:00 2001
From: Carlos Garnacho <carlosg@gnome.org>
Date: Tue, 27 Nov 2018 13:36:26 +0100
Subject: [PATCH] overview: Do not warp pointer to fake crossing event

This is actually papering over bugs in toolkits. On X11 the Xserver will
send crossing events when the stage input shape changes. As those go
end up ignored in GTK+, this warp call aims (and randomly manages) to send
a motion event that wouldn't go unlistened by the drag source window (the
one holding the grab).

This bug actually manifests in other ways, eg. by changing the window
beneath the pointer with alt-tab while DnDing. This should be fixed
altogether in the client side.

https://gitlab.gnome.org/GNOME/gnome-shell/merge_requests/317
---
 js/ui/overview.js | 20 --------------------
 1 file changed, 20 deletions(-)

diff --git a/js/ui/overview.js b/js/ui/overview.js
index ae60e1a24..e92b21e50 100644
--- a/js/ui/overview.js
+++ b/js/ui/overview.js
@@ -2,13 +2,11 @@
 
 const Clutter = imports.gi.Clutter;
 const GLib = imports.gi.GLib;
-const Gtk = imports.gi.Gtk;
 const Meta = imports.gi.Meta;
 const Mainloop = imports.mainloop;
 const Signals = imports.signals;
 const St = imports.gi.St;
 const Shell = imports.gi.Shell;
-const Gdk = imports.gi.Gdk;
 
 const Background = imports.ui.background;
 const DND = imports.ui.dnd;
@@ -158,7 +156,6 @@ var Overview = class {
         this._windowSwitchTimestamp = 0;
         this._lastActiveWorkspaceIndex = -1;
         this._lastHoveredWindow = null;
-        this._needsFakePointerEvent = false;
 
         if (this._initCalled)
             this.init();
@@ -306,19 +303,9 @@ var Overview = class {
         if (this._windowSwitchTimeoutId != 0) {
             Mainloop.source_remove(this._windowSwitchTimeoutId);
             this._windowSwitchTimeoutId = 0;
-            this._needsFakePointerEvent = false;
         }
     }
 
-    _fakePointerEvent() {
-        let display = Gdk.Display.get_default();
-        let deviceManager = display.get_device_manager();
-        let pointer = deviceManager.get_client_pointer();
-        let [gdkScreen, pointerX, pointerY] = pointer.get_position();
-
-        pointer.warp(gdkScreen, pointerX, pointerY);
-    }
-
     _onDragMotion(dragEvent) {
         let targetIsWindow = dragEvent.targetActor &&
                              dragEvent.targetActor._delegate &&
@@ -340,7 +327,6 @@ var Overview = class {
             this._windowSwitchTimeoutId = Mainloop.timeout_add(DND_WINDOW_SWITCH_TIMEOUT,
                 () => {
                     this._windowSwitchTimeoutId = 0;
-                    this._needsFakePointerEvent = true;
                     Main.activateWindow(dragEvent.targetActor._delegate.metaWindow,
                                         this._windowSwitchTimestamp);
                     this.hide();
@@ -643,12 +629,6 @@ var Overview = class {
             Main.layoutManager.hideOverview();
 
         this._syncGrab();
-
-        // Fake a pointer event if requested
-        if (this._needsFakePointerEvent) {
-            this._fakePointerEvent();
-            this._needsFakePointerEvent = false;
-        }
     }
 
     toggle() {