Split UserMetrics into API vs. implementation. Move API to content/public.

chrome/browser/extensions/extension_metrics_module.cc

 // Copyright (c) 2011 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 "chrome/browser/extensions/extension_metrics_module.h"
 
 #include "base/metrics/histogram.h"
 #include "chrome/common/extensions/extension.h"
-#include "content/browser/user_metrics.h"
+#include "content/public/browser/user_metrics.h"
 
 using base::Histogram;
 using base::LinearHistogram;
+using content::UserMetricsAction;
 
 bool MetricsRecordUserActionFunction::RunImpl() {
   std::string name;
   EXTENSION_FUNCTION_VALIDATE(args_->GetString(0, &name));
 
-  UserMetrics::RecordComputedAction(name);
+  content::RecordComputedAction(name);
   return true;
 }
 
 bool MetricsHistogramHelperFunction::GetNameAndSample(std::string* name,
                                                       int* sample) {
   EXTENSION_FUNCTION_VALIDATE(args_->GetString(0, name));
   EXTENSION_FUNCTION_VALIDATE(args_->GetInteger(1, sample));
   return true;
 }
 
@@ skipping 90 matching lines @@
   return RecordValue(name, Histogram::HISTOGRAM, 1, kThreeMinMs, 50, sample);
 }
 
 bool MetricsRecordLongTimeFunction::RunImpl() {
   std::string name;
   int sample;
   EXTENSION_FUNCTION_VALIDATE(GetNameAndSample(&name, &sample));
   static const int kOneHourMs = 60 * 60 * 1000;
   return RecordValue(name, Histogram::HISTOGRAM, 1, kOneHourMs, 50, sample);
 }