exo: Confine windows to primary display

components/exo/wm_helper_ash.cc

Index: components/exo/wm_helper_ash.cc
diff --git a/components/exo/wm_helper_ash.cc b/components/exo/wm_helper_ash.cc
index a7ae4969d558e709bc954cb6a0b46288e3054648..d22aa4b536f4224caa081c12a0bebf9588243a2a 100644
--- a/components/exo/wm_helper_ash.cc
+++ b/components/exo/wm_helper_ash.cc
@@ -60,7 +60,7 @@ const display::ManagedDisplayInfo WMHelperAsh::GetDisplayInfo(
 }
 
 aura::Window* WMHelperAsh::GetContainer(int container_id) {
-  return ash::Shell::GetContainer(ash::Shell::GetRootWindowForNewWindows(),
+  return ash::Shell::GetContainer(ash::Shell::GetPrimaryRootWindow(),

[reveman, 2017/05/04 21:56:11]

nit: please add a TODO with link to bug here to explain that this prevents all
exo clients from using multiple displays

[Dominik Laskowski, 2017/05/04 22:42:09]

Done.

                                   container_id);
 }