Scale the location of drag image for high DPI

ui/views/widget/desktop_aura/desktop_drag_drop_client_aurax11.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/desktop_drag_drop_client_aurax11.h"
 
 #include <X11/Xatom.h>
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 749 matching lines @@
 void DesktopDragDropClientAuraX11::OnWindowDestroyed(aura::Window* window) {
   DCHECK_EQ(target_window_, window);
   target_window_ = NULL;
 }
 
 void DesktopDragDropClientAuraX11::OnMouseMovement(
     const gfx::Point& screen_point,
     int flags,
     base::TimeDelta event_time) {
   if (drag_widget_.get()) {
+    display::Display display =
+        display::Screen::GetScreen()->GetDisplayNearestWindow(
+            drag_widget_->GetNativeWindow());
+    gfx::Point scaled_point = gfx::ScaleToRoundedPoint(
+        screen_point, 1.f / display.device_scale_factor());
     drag_widget_->SetBounds(
-        gfx::Rect(screen_point - drag_widget_offset_,
-                  drag_widget_->GetWindowBoundsInScreen().size()));
+        gfx::Rect(scaled_point - drag_widget_offset_, drag_image_size_));
     drag_widget_->StackAtTop();
   }
 
   const int kModifiers = ui::EF_SHIFT_DOWN | ui::EF_CONTROL_DOWN |
                          ui::EF_ALT_DOWN | ui::EF_COMMAND_DOWN |
                          ui::EF_LEFT_MOUSE_BUTTON |
                          ui::EF_MIDDLE_MOUSE_BUTTON |
                          ui::EF_RIGHT_MOUSE_BUTTON;
   current_modifier_state_ = flags & kModifiers;
 
@@ skipping 406 matching lines @@
 
   gfx::Point location = display::Screen::GetScreen()->GetCursorScreenPoint() -
                         drag_widget_offset_;
   params.bounds = gfx::Rect(location, image.size());
   widget->set_focus_on_creation(false);
   widget->set_frame_type(Widget::FRAME_TYPE_FORCE_NATIVE);
   widget->Init(params);
   widget->SetOpacity(kDragWidgetOpacity);
   widget->GetNativeWindow()->SetName("DragWindow");
 
+  drag_image_size_ = image.size();
   ImageView* image_view = new ImageView();
   image_view->SetImage(image);
-  image_view->SetBounds(0, 0, image.width(), image.height());
+  image_view->SetBoundsRect(gfx::Rect(drag_image_size_));
   widget->SetContentsView(image_view);
   widget->Show();
   widget->GetNativeWindow()->layer()->SetFillsBoundsOpaquely(false);
 
   drag_widget_.reset(widget);
 }
 
 bool DesktopDragDropClientAuraX11::IsValidDragImage(
     const gfx::ImageSkia& image) {
   if (image.isNull())
@@ skipping 10 matching lines @@
     for (int x = 0; x < in_bitmap->width(); ++x) {
       if (SkColorGetA(in_row[x]) > kMinAlpha)
         return true;
     }
   }
 
   return false;
 }
 
 }  // namespace views