Add missing IWYU message_loop.h includes.

device/generic_sensor/platform_sensor_provider_linux.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 "device/generic_sensor/platform_sensor_provider_linux.h"
 
 #include "base/memory/singleton.h"
+#include "base/message_loop/message_loop.h"
 #include "base/task_runner_util.h"
 #include "base/threading/thread.h"
 #include "device/generic_sensor/linux/sensor_data_linux.h"
 #include "device/generic_sensor/platform_sensor_linux.h"
 #include "device/generic_sensor/platform_sensor_reader_linux.h"
 
 namespace device {
 
 // static
 PlatformSensorProviderLinux* PlatformSensorProviderLinux::GetInstance() {
@@ skipping 186 matching lines @@
     mojom::SensorType type,
     const std::string& device_node) {
   DCHECK(CalledOnValidThread());
   auto it = sensor_devices_by_type_.find(type);
   if (it != sensor_devices_by_type_.end() &&
       it->second->device_node == device_node)
     sensor_devices_by_type_.erase(it);
 }
 
 }  // namespace device