Connect SparseHistogram with the rest of stats system

base/metrics/histogram_flattener.h

Index: base/metrics/histogram_flattener.h
diff --git a/base/metrics/histogram_flattener.h b/base/metrics/histogram_flattener.h
index 137ce980a6844879fc41713d0add2f7f2cc9e090..ca05a4f421f415374f4f37d24b9b43f66cbff052 100644
--- a/base/metrics/histogram_flattener.h
+++ b/base/metrics/histogram_flattener.h
@@ -24,14 +24,14 @@ class BASE_EXPORT HistogramFlattener {
   virtual void RecordDelta(const HistogramBase& histogram,
                            const HistogramSamples& snapshot) = 0;
 
-  // Will be called each time a type of Inconsistenies is seen on a histogram,
+  // Will be called each time a type of Inconsistency is seen on a histogram,
   // during inspections done internally in HistogramSnapshotManager class.
-  virtual void InconsistencyDetected(Histogram::Inconsistencies problem) = 0;
+  virtual void InconsistencyDetected(HistogramBase::Inconsistency problem) = 0;
 
-  // Will be called when a type of Inconsistenies is seen for the first time
-  // on a histogram.
+  // Will be called when a type of Inconsistency is seen for the first time on
+  // a histogram.
   virtual void UniqueInconsistencyDetected(
-      Histogram::Inconsistencies problem) = 0;
+      HistogramBase::Inconsistency problem) = 0;
 
   // Will be called when the total logged sample count of a histogram
   // differs from the sum of logged sample count in all the buckets.  The