Refactor of Histogram related code

net/url_request/url_request_throttler_unittest.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 "net/url_request/url_request_throttler_manager.h"
 
 #include "base/memory/scoped_ptr.h"
 #include "base/metrics/histogram.h"
 #include "base/metrics/statistics_recorder.h"
 #include "base/pickle.h"
@@ skipping 210 matching lines @@
     Histogram::SampleSet& original = original_samples_[name];
     Histogram::SampleSet& sample = samples_[name];
 
     Histogram* histogram = StatisticsRecorder::FindHistogram(name);
     if (histogram) {
       ASSERT_EQ(Histogram::kUmaTargetedHistogramFlag, histogram->flags());
 
       histogram->SnapshotSample(&sample);
       // Ensure |original| size is same as |sample|, then subtract original
       // values.
-      original.Resize(*histogram);
+      original.Resize(histogram->bucket_count());
       sample.Subtract(original);
     }
   }
 
   // Ensure we don't accidentally use the originals in our tests.
   original_samples_.clear();
 }
 
 std::ostream& operator<<(std::ostream& out, const base::TimeTicks& time) {
   return out << time.ToInternalValue();
@@ skipping 303 matching lines @@
         FAIL();
     }
 
     scoped_refptr<net::URLRequestThrottlerEntryInterface> entry_after =
         manager.RegisterRequestUrl(GURL("http://www.example.com/"));
     EXPECT_FALSE(entry_after->ShouldRejectRequest(request_));
   }
 }
 
 }  // namespace net