3 files changed, 12 insertions, 1 deletions
diff --git a/ash/host/ash_window_tree_host.h b/ash/host/ash_window_tree_host.h
index 1d1513b..b9c617f 100644
--- a/ash/host/ash_window_tree_host.h
+++ b/ash/host/ash_window_tree_host.h
@@ -53,7 +53,10 @@ class ASH_EXPORT AshWindowTreeHost {
   // mode dual monitors case). If the root window is only associated with one
   // display id, then the other id should be set to
   // gfx::Display::kInvalidDisplayID.
-  virtual void UpdateDisplayID(int64 id1, int64 id2) {};
+  virtual void UpdateDisplayID(int64 id1, int64 id2) {}
+
+  // Stop listening for events in preparation for shutdown.
+  virtual void PrepareForShutdown() {}
 };
 
 }  // namespace ash
diff --git a/ash/host/ash_window_tree_host_x11.cc b/ash/host/ash_window_tree_host_x11.cc
index eff9ba6..beb129f 100644
--- a/ash/host/ash_window_tree_host_x11.cc
+++ b/ash/host/ash_window_tree_host_x11.cc
@@ -19,9 +19,11 @@
 #include "ui/aura/client/screen_position_client.h"
 #include "ui/aura/env.h"
 #include "ui/aura/window.h"
+#include "ui/aura/window_event_dispatcher.h"
 #include "ui/base/x/x11_util.h"
 #include "ui/events/event.h"
 #include "ui/events/event_utils.h"
+#include "ui/events/platform/platform_event_source.h"
 #include "ui/events/x/device_data_manager.h"
 #include "ui/events/x/device_list_cache_x.h"
 #include "ui/events/x/touch_factory_x11.h"
@@ -129,6 +131,11 @@ void AshWindowTreeHostX11::UpdateDisplayID(int64 id1, int64 id2) {
   display_ids_.second = id2;
 }
 
+void AshWindowTreeHostX11::PrepareForShutdown() {
+  if (ui::PlatformEventSource::GetInstance())
+    ui::PlatformEventSource::GetInstance()->RemovePlatformEventDispatcher(this);
+}
+
 void AshWindowTreeHostX11::SetBounds(const gfx::Rect& bounds) {
   WindowTreeHostX11::SetBounds(bounds);
   if (pointer_barriers_) {
diff --git a/ash/host/ash_window_tree_host_x11.h b/ash/host/ash_window_tree_host_x11.h
index 8b998be..1a3335d 100644
--- a/ash/host/ash_window_tree_host_x11.h
+++ b/ash/host/ash_window_tree_host_x11.h
@@ -33,6 +33,7 @@ class ASH_EXPORT AshWindowTreeHostX11 : public AshWindowTreeHost,
   virtual gfx::Insets GetHostInsets() const OVERRIDE;
   virtual aura::WindowTreeHost* AsWindowTreeHost() OVERRIDE;
   virtual void UpdateDisplayID(int64 id1, int64 id2) OVERRIDE;
+  virtual void PrepareForShutdown() OVERRIDE;
 
   // aura::WindowTreehost:
   virtual void SetBounds(const gfx::Rect& bounds) OVERRIDE;