Use the location where FileDescriptorWatcher is created to track the libevent handlers

ui/events/ozone/evdev/event_converter_evdev_impl.cc

 // Copyright 2014 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/ozone/evdev/event_converter_evdev_impl.h"
 
 #include <errno.h>
 #include <linux/input.h>
 #include <stddef.h>
 
@@ skipping 30 matching lines @@
                           path,
                           id,
                           devinfo.device_type(),
                           devinfo.name(),
                           devinfo.vendor_id(),
                           devinfo.product_id()),
       input_device_fd_(std::move(fd)),
       has_keyboard_(devinfo.HasKeyboard()),
       has_touchpad_(devinfo.HasTouchpad()),
       has_caps_lock_led_(devinfo.HasLedEvent(LED_CAPSL)),
+      controller_(FROM_HERE),
       cursor_(cursor),
       dispatcher_(dispatcher) {}
 
 EventConverterEvdevImpl::~EventConverterEvdevImpl() {
   DCHECK(!enabled_);
 }
 
 void EventConverterEvdevImpl::OnFileCanReadWithoutBlocking(int fd) {
   TRACE_EVENT1("evdev", "EventConverterEvdevImpl::OnFileCanReadWithoutBlocking",
                "fd", fd);
@@ skipping 190 matching lines @@
   dispatcher_->DispatchMouseMoveEvent(
       MouseMoveEventParams(input_device_.id, EF_NONE, cursor_->GetLocation(),
                            PointerDetails(EventPointerType::POINTER_TYPE_MOUSE),
                            TimeTicksFromInputEvent(input)));
 
   x_offset_ = 0;
   y_offset_ = 0;
 }
 
 }  // namespace ui