Add tests for drag and drop for Linux Aura

ui/views/widget/desktop_aura/desktop_drag_drop_client_aurax11.h

 // Copyright (c) 2012 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_DRAG_DROP_CLIENT_AURAX11_H_
 #define UI_VIEWS_WIDGET_DESKTOP_AURA_DESKTOP_DRAG_DROP_CLIENT_AURAX11_H_
 
 #include <set>
 #include <X11/Xlib.h>
 
@@ skipping 79 matching lines @@
   virtual bool IsDragDropInProgress() OVERRIDE;
 
   // Overridden from aura::WindowObserver:
   virtual void OnWindowDestroyed(aura::Window* window) OVERRIDE;
 
   // Overridden from X11WholeScreenMoveLoopDelegate:
   virtual void OnMouseMovement(XMotionEvent* event) OVERRIDE;
   virtual void OnMouseReleased() OVERRIDE;
   virtual void OnMoveLoopEnded() OVERRIDE;
 
+ protected:
+  // The following methods are virtual for the sake of testing.
+
+  // Returns the topmost X11 window at |screen_point| and returns it if it is

[varkha, 2014/05/07 03:11:08]

Nit: Do you want to rephrase it a bit (remove repeated returns)?

[pkotwicz, 2014/05/07 15:16:36]

Done.

+  // Xdnd aware. Returns NULL otherwise.
+  virtual ::Window FindWindowFor(const gfx::Point& screen_point);
+
+  // Sends |xev| to |xid|, optionally short circuiting the round trip to the X
+  // server.
+  virtual void SendXClientEvent(::Window xid, XEvent* xev);
+
  private:
   enum SourceState {
     // |source_current_window_| will receive a drop once we receive an
     // XdndStatus from it.
     SOURCE_STATE_PENDING_DROP,
 
     // The move looped will be ended once we receive XdndFinished from
     // |source_current_window_|. We should not send XdndPosition to
     // |source_current_window_| while in this state.
     SOURCE_STATE_DROPPED,
@@ skipping 49 matching lines @@
   void CompleteXdndPosition(::Window source_window,
                             const gfx::Point& screen_point);
 
   void SendXdndEnter(::Window dest_window);
   void SendXdndLeave(::Window dest_window);
   void SendXdndPosition(::Window dest_window,
                         const gfx::Point& screen_point,
                         unsigned long event_time);
   void SendXdndDrop(::Window dest_window);
 
-  // Sends |xev| to |xid|, optionally short circuiting the round trip to the X
-  // server.
-  void SendXClientEvent(::Window xid, XEvent* xev);
-
   // A nested message loop that notifies this object of events through the
   // X11WholeScreenMoveLoopDelegate interface.
   X11WholeScreenMoveLoop move_loop_;
 
   aura::Window* root_window_;
 
   Display* xdisplay_;
   ::Window xwindow_;
 
   ui::X11AtomCache atom_cache_;
@@ skipping 63 matching lines @@
   gfx::NativeCursor move_grab_cursor_;
 
   base::WeakPtrFactory<DesktopDragDropClientAuraX11> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(DesktopDragDropClientAuraX11);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_WIDGET_DESKTOP_AURA_DESKTOP_DRAG_DROP_CLIENT_AURAX11_H_