[UMA] Fix a crash on logging user actions posted from a non-UI thread.

content/browser/plugin_loader_posix.cc

 // Copyright (c) 2012 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 "content/browser/plugin_loader_posix.h"
 
 #include "base/bind.h"
 #include "base/message_loop/message_loop.h"
 #include "base/message_loop/message_loop_proxy.h"
 #include "base/metrics/histogram.h"
-#include "base/metrics/user_metrics.h"
 #include "content/browser/utility_process_host_impl.h"
 #include "content/common/child_process_host_impl.h"
 #include "content/common/plugin_list.h"
 #include "content/common/utility_messages.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/plugin_service.h"
+#include "content/public/browser/user_metrics.h"
 
 namespace content {
 
 PluginLoaderPosix::PluginLoaderPosix()
     : next_load_index_(0) {
 }
 
 void PluginLoaderPosix::GetPlugins(
     const PluginService::GetPluginsCallback& callback) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
@@ skipping 183 matching lines @@
 
   HISTOGRAM_TIMES("PluginLoaderPosix.LoadDone",
                   (base::TimeTicks::Now() - load_start_time_)
                       * base::Time::kMicrosecondsPerMillisecond);
   load_start_time_ = base::TimeTicks();
 
   return true;
 }
 
 }  // namespace content