Fix device_event_log component build, make NonThreadSafe (Take 2)

components/device_event_log.gypi

 # Copyright 2015 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.
 
 {
   'targets': [
     {
       'target_name': 'device_event_log_component',
-      'type': 'static_library',
+      'type': '<(component)',
       'dependencies': [
         '../base/base.gyp:base',
         '../net/net.gyp:net',
       ],
       'include_dirs': [
         '..',
       ],
+      'defines': [
+        'DEVICE_EVENT_LOG_IMPLEMENTATION',
+      ],
       'sources': [
         'device_event_log/device_event_log.cc',
         'device_event_log/device_event_log.h',
         'device_event_log/device_event_log_impl.cc',
         'device_event_log/device_event_log_impl.h',
       ],
     },
   ],
 }