Histogram type support in HistogramBase and remove SetRangeDescription function

base/metrics/histogram_base.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_base.h"
 
 #include <climits>
 
+#include "base/logging.h"
 #include "base/json/json_string_value_serializer.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/values.h"
 
 namespace base {
 
+std::string HistogramTypeToString(HistogramType type) {
+  switch(type) {
+    case HISTOGRAM:
+      return "HISTOGRAM";
+    case LINEAR_HISTOGRAM:
+      return "LINEAR_HISTOGRAM";
+    case BOOLEAN_HISTOGRAM:
+      return "BOOLEAN_HISTOGRAM";
+    case CUSTOM_HISTOGRAM:
+      return "CUSTOM_HISTOGRAM";
+    case SPARSE_HISTOGRAM:
+      return "SPARSE_HISTOGRAM";
+    default:
+      NOTREACHED();
+  }
+  return "UNKNOWN";
+}
+
 const HistogramBase::Sample HistogramBase::kSampleType_MAX = INT_MAX;
 
 HistogramBase::HistogramBase(const std::string& name)
     : histogram_name_(name),
       flags_(kNoFlags) {}
 
 HistogramBase::~HistogramBase() {}
 
 void HistogramBase::SetFlags(int32 flags) {
   flags_ |= flags;
@@ skipping 14 matching lines @@
   DictionaryValue root;
   root.SetString("name", histogram_name());
   root.SetInteger("count", count);
   root.SetInteger("flags", flags());
   root.Set("params", parameters.release());
   root.Set("buckets", buckets.release());
   serializer.Serialize(root);
 }
 
 }  // namespace base