Add pointer id to the WebMouseEvent's constructors

ui/events/blink/web_input_event.cc

 // 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 "ui/events/blink/web_input_event.h"
 
 #include "ui/events/base_event_utils.h"
 #include "ui/events/blink/blink_event_util.h"
 #include "ui/events/blink/blink_features.h"
 #include "ui/events/event.h"
@@ skipping 400 matching lines @@
     case ET_MOUSE_DRAGGED:
       type = blink::WebInputEvent::kMouseMove;
       break;
     default:
       NOTIMPLEMENTED() << "Received unexpected event: " << event.type();
       break;
   }
 
   blink::WebMouseEvent webkit_event(
       type, EventFlagsToWebEventModifiers(event.flags()),
-      EventTimeStampToSeconds(event.time_stamp()));
+      EventTimeStampToSeconds(event.time_stamp()), event.pointer_details().id);
   webkit_event.button = blink::WebMouseEvent::Button::kNoButton;
   int button_flags = event.flags();
   if (event.type() == ET_MOUSE_PRESSED || event.type() == ET_MOUSE_RELEASED) {
     // We want to use changed_button_flags() for mouse pressed & released.
     // These flags can be used only if they are set which is not always the case
     // (see e.g. GetChangedMouseButtonFlagsFromNative() in events_win.cc).
     if (event.changed_button_flags())
       button_flags = event.changed_button_flags();
   }
 
@@ skipping 45 matching lines @@
   webkit_event.tilt_x = roundf(event.pointer_details().tilt_x);
   webkit_event.tilt_y = roundf(event.pointer_details().tilt_y);
   webkit_event.force = event.pointer_details().force;
   webkit_event.pointer_type =
       EventPointerTypeToWebPointerType(event.pointer_details().pointer_type);
 
   return webkit_event;
 }
 
 }  // namespace ui