X11: Add TestDesktopScreenX11 to simulate mouse movement in ui tests

ui/views/widget/desktop_aura/desktop_screen_x11.h

 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef UI_VIEWS_WIDGET_DESKTOP_AURA_DESKTOP_SCREEN_X11_H_
 #define UI_VIEWS_WIDGET_DESKTOP_AURA_DESKTOP_SCREEN_X11_H_
 
 #include <stdint.h>
 
 #include <memory>
 
 #include "base/macros.h"
 #include "base/timer/timer.h"
 #include "ui/display/display_change_notifier.h"
 #include "ui/display/screen.h"
 #include "ui/events/platform/platform_event_dispatcher.h"
+#include "ui/gfx/geometry/point.h"
 #include "ui/gfx/x/x11_atom_cache.h"
 #include "ui/views/views_export.h"
 
 typedef unsigned long XID;
 typedef XID Window;
 typedef struct _XDisplay Display;
 
 namespace views {
 class DesktopScreenX11Test;
 
@@ skipping 68 matching lines @@
   // Dispatch().
   std::unique_ptr<base::OneShotTimer> configure_timer_;
 
   display::DisplayChangeNotifier change_notifier_;
 
   ui::X11AtomCache atom_cache_;
 
   DISALLOW_COPY_AND_ASSIGN(DesktopScreenX11);
 };
 
+class VIEWS_EXPORT TestDesktopScreenX11 : public DesktopScreenX11 {

[sky, 2016/09/08 23:41:24]

Document what this class does and why it's needed. Also, it should be in its own
header that is only built in tests.

[Tom (Use chromium acct), 2016/09/09 01:14:11]

Done.

+ public:
+  TestDesktopScreenX11();
+  ~TestDesktopScreenX11() override;
+
+  gfx::Point GetCursorScreenPoint() override;
+  void SetCursorScreenPoint(const gfx::Point& point);
+
+ private:
+  gfx::Point cursor_screen_point_;
+
+  DISALLOW_COPY_AND_ASSIGN(TestDesktopScreenX11);
+};
+
+VIEWS_EXPORT TestDesktopScreenX11* GetTestDesktopScreenX11();
+
 }  // namespace views
 
 #endif  // UI_VIEWS_WIDGET_DESKTOP_AURA_DESKTOP_SCREEN_X11_H_