Connect SparseHistogram with the rest of stats system

base/metrics/histogram_base.h

 // 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.
 
 #ifndef BASE_METRICS_HISTOGRAM_BASE_H_
 #define BASE_METRICS_HISTOGRAM_BASE_H_
 
 #include <string>
 
 #include "base/base_export.h"
@@ skipping 52 matching lines @@
     // If we observe this flag on a histogram being aggregated into after IPC,
     // then we are running in a single process mode, and the aggregation should
     // not take place (as we would be aggregating back into the source
     // histogram!).
     kIPCSerializationSourceFlag = 0x10,
 
     // Only for Histogram and its sub classes: fancy bucket-naming support.
     kHexRangePrintingFlag = 0x8000,
   };
 
+  // Histogram data inconsistency types.
+  enum Inconsistency {
+    NO_INCONSISTENCIES = 0x0,
+    RANGE_CHECKSUM_ERROR = 0x1,
+    BUCKET_ORDER_ERROR = 0x2,
+    COUNT_HIGH_ERROR = 0x4,
+    COUNT_LOW_ERROR = 0x8,
+
+    NEVER_EXCEEDED_VALUE = 0x10
+  };
+
   explicit HistogramBase(const std::string& name);
   virtual ~HistogramBase();
 
   std::string histogram_name() const { return histogram_name_; }
 
   // Operations with Flags enum.
   int32 flags() const { return flags_; }
   void SetFlags(int32 flags);
   void ClearFlags(int32 flags);
 
@@ skipping 13 matching lines @@
   void AddBoolean(bool value);
 
   virtual void AddSamples(const HistogramSamples& samples) = 0;
   virtual bool AddSamplesFromPickle(PickleIterator* iter) = 0;
 
   // Serialize the histogram info into |pickle|.
   // Note: This only serializes the construction arguments of the histogram, but
   // does not serialize the samples.
   bool SerializeInfo(Pickle* pickle) const;
 
+  // Try to find out data corruption from histogram and the samples.
+  // The returned value is a combination of Inconsistency enum.
+  virtual int FindCorruption(const HistogramSamples& samples) const;
+
   // Snapshot the current complete set of sample data.
   // Override with atomic/locked snapshot if needed.
   virtual scoped_ptr<HistogramSamples> SnapshotSamples() const = 0;
 
   // The following methods provide graphical histogram displays.
   virtual void WriteHTMLGraph(std::string* output) const = 0;
   virtual void WriteAscii(std::string* output) const = 0;
 
   // Produce a JSON representation of the histogram. This is implemented with
   // the help of GetParameters and GetCountAndBucketData; overwrite them to
@@ skipping 14 matching lines @@
  private:
   const std::string histogram_name_;
   int32 flags_;
 
   DISALLOW_COPY_AND_ASSIGN(HistogramBase);
 };
 
 }  // namespace base
 
 #endif  // BASE_METRICS_HISTOGRAM_BASE_H_