Refactor of Histogram related code

base/metrics/histogram_snapshot_manager.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 "base/metrics/histogram_snapshot_manager.h"
 
 #include "base/metrics/statistics_recorder.h"
 
 using base::Histogram;
 using base::StatisticsRecorder;
@@ skipping 58 matching lines @@
     return;
   }
 
   // Find the already recorded stats, or create an empty set. Remove from our
   // snapshot anything that we've already recorded.
   LoggedSampleMap::iterator it = logged_samples_.find(histogram_name);
   Histogram::SampleSet* already_logged;
   if (logged_samples_.end() == it) {
     // Add new entry
     already_logged = &logged_samples_[histogram.histogram_name()];
-    already_logged->Resize(histogram);  // Complete initialization.
+    // Complete initialization.
+    already_logged->Resize(histogram.bucket_count());
   } else {
     already_logged = &(it->second);
     int64 discrepancy(already_logged->TotalCount() -
                       already_logged->redundant_count());
     if (discrepancy) {
       NOTREACHED();  // Already_logged has become corrupt.
       int problem = static_cast<int>(discrepancy);
       if (problem != discrepancy)
         problem = INT_MAX;
       histogram_flattener_->SnapshotProblemResolved(problem);
       // With no valid baseline, we'll act like we've recorded everything in our
       // snapshot.
       already_logged->Subtract(*already_logged);
       already_logged->Add(snapshot);
     }
     // Deduct any stats we've already logged from our snapshot.
     snapshot.Subtract(*already_logged);
   }
 
   // Snapshot now contains only a delta to what we've already_logged.
   if (snapshot.redundant_count() > 0) {
     histogram_flattener_->RecordDelta(histogram, snapshot);
     // Add new data into our running total.
     already_logged->Add(snapshot);
   }
 }
 }  // namespace base