[gnome-shell] keyboard: Handle no-window case in FocusTracker

[Florian Müllner <fmuellner src gnome org>]

commit 0dee82fb9fa974ebdb4dd77fd85535a6edf207fd
Author: Florian Müllner <fmuellner gnome org>
Date:   Tue Jul 17 01:36:38 2018 +0200

    keyboard: Handle no-window case in FocusTracker
    
    For windows, the cursor location needs to be adjusted by the frame
    offsets. However we cannot assume that there is a window, as the
    shell itself can have the key focus.
    
    https://gitlab.gnome.org/GNOME/gnome-shell/issues/414

 js/ui/keyboard.js | 18 +++++++++++++-----
 1 file changed, 13 insertions(+), 5 deletions(-)
---
diff --git a/js/ui/keyboard.js b/js/ui/keyboard.js
index 41942eeaa..1fefb8c6c 100644
--- a/js/ui/keyboard.js
+++ b/js/ui/keyboard.js
@@ -533,17 +533,25 @@ var FocusTracker = new Lang.Class({
     },
 
     _setCurrentRect(rect) {
-        let frameRect = this._currentWindow.get_frame_rect();
-        rect.x -= frameRect.x;
-        rect.y -= frameRect.y;
+        if (this._currentWindow) {
+            let frameRect = this._currentWindow.get_frame_rect();
+            rect.x -= frameRect.x;
+            rect.y -= frameRect.y;
+        }
 
         this._rect = rect;
         this.emit('position-changed');
     },
 
     getCurrentRect() {
-        let frameRect = this._currentWindow.get_frame_rect();
-        let rect = { x: this._rect.x + frameRect.x, y: this._rect.y + frameRect.y, width: this._rect.width, 
height: this._rect.height };
+        let rect = { x: this._rect.x, y: this._rect.y,
+                     width: this._rect.width, height: this._rect.height };
+
+        if (this._currentWindow) {
+            let frameRect = this._currentWindow.get_frame_rect();
+            rect.x += frameRect.x;
+            rect.y += frameRect.y;
+        }
 
         return rect;
     }