aura: Add flag to indicate if a drag session is started with touch or mouse.

ui/views/controls/menu/menu_controller.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/controls/menu/menu_controller.h"
 
 #include "base/i18n/case_conversion.h"
 #include "base/i18n/rtl.h"
 #include "base/run_loop.h"
 #include "base/time.h"
@@ skipping 845 matching lines @@
   item->PaintButton(canvas.get(), MenuItemView::PB_FOR_DRAG);
 
   OSExchangeData data;
   item->GetDelegate()->WriteDragData(item, &data);
   drag_utils::SetDragImageOnDataObject(*canvas, item->size(),
                                        press_loc.OffsetFromOrigin(),
                                        &data);
   StopScrolling();
   int drag_ops = item->GetDelegate()->GetDragOperations(item);
   drag_in_progress_ = true;
-  item->GetWidget()->RunShellDrag(NULL, data, widget_loc, drag_ops);
+  // TODO(varunjain): Properly determine and send DRAG_EVENT_SOURCE below.
+  item->GetWidget()->RunShellDrag(NULL, data, widget_loc, drag_ops,
+      ui::DragDropTypes::DRAG_EVENT_SOURCE_MOUSE);
   drag_in_progress_ = false;
 
   if (GetActiveInstance() == this) {
     if (showing_) {
       // We're still showing, close all menus.
       CloseAllNestedMenus();
       Cancel(EXIT_ALL);
     }  // else case, drop was on us.
   }  // else case, someone canceled us, don't do anything
 }
@@ skipping 1259 matching lines @@
 
 gfx::Screen* MenuController::GetScreen() {
 #if defined(USE_AURA)
   return gfx::Screen::GetScreenFor(root_window_);
 #else
   return gfx::Screen::GetNativeScreen();
 #endif
 }
 
 }  // namespace views