Keep the mouse cursor within desktop

ui/aura/root_window_host_linux.h

Index: ui/aura/root_window_host_linux.h
diff --git a/ui/aura/root_window_host_linux.h b/ui/aura/root_window_host_linux.h
index 5b4c96a1b0b3c5cd5fee5c844c4ef5183620a58c..83f59c03cd039bef4e67fae410db84d91542e31f 100644
--- a/ui/aura/root_window_host_linux.h
+++ b/ui/aura/root_window_host_linux.h
@@ -11,19 +11,22 @@
 // Get rid of a macro from Xlib.h that conflicts with Aura's RootWindow class.
 #undef RootWindow
 
+#include "base/memory/scoped_ptr.h"
 #include "base/message_loop.h"
 #include "ui/aura/root_window_host.h"
 #include "ui/gfx/rect.h"
 
 namespace aura {
 
-class RootWindowHostLinux : public RootWindowHost {
+class RootWindowHostLinux : public RootWindowHost,
+                            public MessageLoop::Dispatcher {
  public:
   explicit RootWindowHostLinux(const gfx::Rect& bounds);
   virtual ~RootWindowHostLinux();
 
-  // Handles an event targeted at this host's window.
-  base::MessagePumpDispatcher::DispatchStatus Dispatch(XEvent* xev);
+  // Overridden from Dispatcher overrides:
+  virtual base::MessagePumpDispatcher::DispatchStatus
+      Dispatch(XEvent* xev) OVERRIDE;
 
  private:
   // RootWindowHost Overrides.
@@ -78,6 +81,8 @@ class RootWindowHostLinux : public RootWindowHost {
   // True if the window should be focused when the window is shown.
   bool focus_when_shown_;
 
+  scoped_array<XID> pointer_barriers_;
+
   DISALLOW_COPY_AND_ASSIGN(RootWindowHostLinux);
 };