[DataTransfer] setDragImage() y offset is ignored

ui/views/widget/desktop_aura/x11_whole_screen_move_loop.cc

 // 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.
 
 #include "ui/views/widget/desktop_aura/x11_whole_screen_move_loop.h"
 
 #include <X11/Xlib.h>
 // Get rid of a macro from Xlib.h that conflicts with Aura's RootWindow class.
 #undef RootWindow
 
@@ skipping 262 matching lines @@
   grab_input_window_ = None;
 
   in_move_loop_ = false;
   quit_closure_.Run();
 }
 
 void X11WholeScreenMoveLoop::SetDragImage(const gfx::ImageSkia& image,
                                           gfx::Vector2dF offset) {
   drag_image_ = image;
   drag_offset_ = offset;
-  // Reset the Y offset, so that the drag-image is always just below the cursor,

[spartha, 2014/06/20 11:19:00]

This looks like more of a UX descision. But this causes the
dataTransfer.setDragImage to ignore the y offset. Is this delibrate? 

-  // so that it is possible to see where the cursor is going.
-  drag_offset_.set_y(0.f);
 }
 
 bool X11WholeScreenMoveLoop::GrabPointerAndKeyboard(gfx::NativeCursor cursor) {
   XDisplay* display = gfx::GetXDisplay();
   XGrabServer(display);
 
   XUngrabPointer(display, CurrentTime);
   int ret = XGrabPointer(
       display,
       grab_input_window_,
@@ skipping 88 matching lines @@
     for (int x = 0; x < in_bitmap->width(); ++x) {
       if (SkColorGetA(in_row[x]) > kMinAlpha)
         return true;
     }
   }
 
   return false;
 }
 
 }  // namespace views