[Sensors] Improvements in shared buffer managing

device/generic_sensor/BUILD.gn

 # 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.
 
 import("//build/config/features.gni")
 
 if (is_android) {
   import("//build/config/android/rules.gni")  # For generate_jni().
 }
 
 source_set("generic_sensor") {
   sources = [
     "platform_sensor.cc",
     "platform_sensor.h",
     "platform_sensor_android.cc",
     "platform_sensor_android.h",
     "platform_sensor_provider.h",
     "platform_sensor_provider_android.cc",
     "platform_sensor_provider_base.cc",
     "platform_sensor_provider_base.h",
     "platform_sensor_provider_default.cc",
     "sensor_impl.cc",
     "sensor_impl.h",
     "sensor_provider_impl.cc",
     "sensor_provider_impl.h",
   ]
 
   deps = [
     "//base",
+    "//device/base/synchronization",
     "//device/generic_sensor/public/interfaces",
   ]
 
   if (is_android) {
     sources += [
       "android/sensors_jni_registrar.cc",
       "android/sensors_jni_registrar.h",
     ]
     sources -= [ "platform_sensor_provider_default.cc" ]
 
@@ skipping 30 matching lines @@
     "fake_platform_sensor_provider.cc",
     "fake_platform_sensor_provider.h",
   ]
 
   public_deps = [
     ":generic_sensor",
     "//base",
     "//device/generic_sensor/public/interfaces",
   ]
 }