Bug 1555866 - [Wayland] Don't position windows with zero height/width, r=jhorak

Differential Revision: https://phabricator.services.mozilla.com/D33492

--HG--
extra : moz-landing-system : lando

widget/gtk/nsWindow.cpp

@@ -1256,6 +1256,12 @@ void nsWindow::NativeMoveResizeWaylandPopup(GdkPoint* aPosition,
       GdkWindow*, const GdkRectangle*, GdkGravity, GdkGravity, GdkAnchorHints,
       gint, gint))dlsym(RTLD_DEFAULT, "gdk_window_move_to_rect");
 
+  // Compositor may be confused by windows with width/height = 0
+  // and positioning such windows leads to Bug 1555866.
+  if (!AreBoundsSane()) {
+    return;
+  }
+
   if (aSize) {
     gtk_window_resize(GTK_WINDOW(mShell), aSize->width, aSize->height);
   }
@@ -1265,8 +1271,7 @@ void nsWindow::NativeMoveResizeWaylandPopup(GdkPoint* aPosition,
   // Use standard gtk_window_move() instead of gdk_window_move_to_rect() when:
   // - gdk_window_move_to_rect() is not available
   // - the widget doesn't have a valid GdkWindow
-  // - the widget hasn't beed positioned yet
-  if (!sGdkWindowMoveToRect || !gdkWindow || !AreBoundsSane()) {
+  if (!sGdkWindowMoveToRect || !gdkWindow) {
     gtk_window_move(GTK_WINDOW(mShell), aPosition->x, aPosition->y);
     return;
   }