Disable drag and drop when we use stylus on Windows

third_party/WebKit/Source/core/input/MouseEventManager.cpp

 // Copyright 2016 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 "core/input/MouseEventManager.h"
 
 #include "core/clipboard/DataObject.h"
 #include "core/clipboard/DataTransfer.h"
 #include "core/dom/Element.h"
 #include "core/dom/ElementTraversal.h"
@@ skipping 737 matching lines @@
   //    the next mouse release event seen by the EventHandler.
   // 3. When pressing Esc key while dragging and the object is outside of the
   //    we get a mouse leave event here
   if (event.Event().button != WebPointerProperties::Button::kLeft ||
       event.Event().GetType() == WebInputEvent::kMouseLeave)
     mouse_pressed_ = false;
 
   if (!mouse_pressed_)
     return WebInputEventResult::kNotHandled;
 
+  if (event.Event().pointer_type ==
+      blink::WebPointerProperties::PointerType::kPen)
+    return WebInputEventResult::kNotHandled;
+
   if (HandleDrag(event, DragInitiator::kMouse))
     return WebInputEventResult::kHandledSystem;
 
   Node* target_node = event.InnerNode();
   if (!target_node)
     return WebInputEventResult::kNotHandled;
 
   LayoutObject* layout_object = target_node->GetLayoutObject();
   if (!layout_object) {
     Node* parent = FlatTreeTraversal::Parent(*target_node);
@@ skipping 315 matching lines @@
 
 void MouseEventManager::SetClickCount(int click_count) {
   click_count_ = click_count;
 }
 
 bool MouseEventManager::MouseDownMayStartDrag() {
   return mouse_down_may_start_drag_;
 }
 
 }  // namespace blink