Add ownership-transfer to histogram management calls.

chromecast/base/metrics/grouped_histogram.cc

 // Copyright 2014 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 "chromecast/base/metrics/grouped_histogram.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include "base/lazy_instance.h"
@@ skipping 125 matching lines @@
                           GroupedHistogram::Sample minimum,
                           GroupedHistogram::Sample maximum,
                           uint32_t bucket_count,
                           int32_t flags) {
   DCHECK(base::StatisticsRecorder::IsActive());
   DCHECK(base::Histogram::InspectConstructionArguments(
       name, &minimum, &maximum, &bucket_count));
   DCHECK(!base::StatisticsRecorder::FindHistogram(name))
       << "Failed to preregister " << name << ", Histogram already exists.";
 
-  // To avoid racy destruction at shutdown, the following will be leaked.
-  base::BucketRanges* ranges = new base::BucketRanges(bucket_count + 1);
-  base::Histogram::InitializeBucketRanges(minimum, maximum, ranges);
+  scoped_ptr<base::BucketRanges> ranges(
+      new base::BucketRanges(bucket_count + 1));
+  base::Histogram::InitializeBucketRanges(minimum, maximum, ranges.get());
   const base::BucketRanges* registered_ranges =
-      base::StatisticsRecorder::RegisterOrDeleteDuplicateRanges(ranges);
+      base::StatisticsRecorder::RegisterOrDeleteDuplicateRanges(
+          std::move(ranges));
 
-  GroupedHistogram* tentative_histogram =
-      new GroupedHistogram(name, minimum, maximum, registered_ranges);
+  scoped_ptr<GroupedHistogram> tentative_histogram(
+      new GroupedHistogram(name, minimum, maximum, registered_ranges));
 
   tentative_histogram->SetFlags(flags);
+  const void* allocated_histogram = tentative_histogram.get();
   base::HistogramBase* histogram =
-      base::StatisticsRecorder::RegisterOrDeleteDuplicate(tentative_histogram);
+      base::StatisticsRecorder::RegisterOrDeleteDuplicate(
+          std::move(tentative_histogram));
 
-  DCHECK_EQ(histogram, tentative_histogram);
+  DCHECK_EQ(histogram, allocated_histogram);
   DCHECK_EQ(base::HISTOGRAM, histogram->GetHistogramType());
   DCHECK(histogram->HasConstructionArguments(minimum, maximum, bucket_count));
 }
 
 } // namespace
 
 void PreregisterAllGroupedHistograms() {
   base::StatisticsRecorder::Initialize();
   for (size_t i = 0; i < arraysize(kHistogramsToGroup); ++i) {
     PreregisterHistogram(
         kHistogramsToGroup[i].name,
         kHistogramsToGroup[i].minimum,
         kHistogramsToGroup[i].maximum,
         kHistogramsToGroup[i].bucket_count,
         base::HistogramBase::kUmaTargetedHistogramFlag);
   }
 }
 
 void TagAppStartForGroupedHistograms(const std::string& app_name) {
   base::AutoLock lock(g_current_app.Get().lock);
   g_current_app.Get().app_name = app_name;
 }
 
 } // namespace metrics
 } // namespace chromecast