Use factory to create histograms, and refcounts to track lifetimes...

net/base/sdch_manager.cc

 // Copyright (c) 2006-2008 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 "base/base64.h"
 #include "base/field_trial.h"
 #include "base/histogram.h"
 #include "base/logging.h"
 #include "base/sha2.h"
 #include "base/string_util.h"
@@ skipping 14 matching lines @@
 // static
 SdchManager* SdchManager::global_;
 
 // static
 SdchManager* SdchManager::Global() {
   return global_;
 }
 
 // static
 void SdchManager::SdchErrorRecovery(ProblemCodes problem) {
-  static LinearHistogram histogram("Sdch3.ProblemCodes_4", MIN_PROBLEM_CODE,
-                                   MAX_PROBLEM_CODE - 1, MAX_PROBLEM_CODE);
-  histogram.SetFlags(kUmaTargetedHistogramFlag);
-  histogram.Add(problem);
+  static scoped_refptr<Histogram> histogram =
+      LinearHistogram::LinearHistogramFactoryGet("Sdch3.ProblemCodes_4",
+          MIN_PROBLEM_CODE + 1, MAX_PROBLEM_CODE - 1, MAX_PROBLEM_CODE);
+  histogram->SetFlags(kUmaTargetedHistogramFlag);
+  histogram->Add(problem);
 }
 
 // static
 void SdchManager::ClearBlacklistings() {
   Global()->blacklisted_domains_.clear();
   Global()->exponential_blacklist_count.clear();
 }
 
 // static
 void SdchManager::ClearDomainBlacklisting(const std::string& domain) {
@@ skipping 482 matching lines @@
   if (enable) {
     allow_latency_experiment_.insert(url.host());
     return;
   }
   ExperimentSet::iterator it = allow_latency_experiment_.find(url.host());
   if (allow_latency_experiment_.end() == it)
     return;  // It was already erased, or never allowed.
   SdchErrorRecovery(LATENCY_TEST_DISALLOWED);
   allow_latency_experiment_.erase(it);
 }