Add LOCAL_ prefix to non-UMA histogram macros.

base/metrics/sparse_histogram.h

Index: base/metrics/sparse_histogram.h
diff --git a/base/metrics/sparse_histogram.h b/base/metrics/sparse_histogram.h
index 07d56603a5d8b4b7a85caadedbbf67d6dba39215..35e1ec28ba8f3ceb044068b96544e793006b9890 100644
--- a/base/metrics/sparse_histogram.h
+++ b/base/metrics/sparse_histogram.h
@@ -28,30 +28,13 @@ namespace base {
       histogram->Add(sample); \
     } while (0)
 
-#define HISTOGRAM_SPARSE_SLOWLY(name, sample) \
+#define LOCAL_HISTOGRAM_SPARSE_SLOWLY(name, sample) \
     HISTOGRAM_SPARSE_COMMON(name, sample, base::HistogramBase::kNoFlags)
 
 #define UMA_HISTOGRAM_SPARSE_SLOWLY(name, sample) \
     HISTOGRAM_SPARSE_COMMON(name, sample, \
                             base::HistogramBase::kUmaTargetedHistogramFlag)
 
-//------------------------------------------------------------------------------
-// Define debug only version of macros.
-#ifndef NDEBUG
-
-#define DHISTOGRAM_SPARSE_SLOWLY(name, sample) \
-    HISTOGRAM_SPARSE_SLOWLY(name, sample)
-
-#else  // NDEBUG
-
-#define DHISTOGRAM_SPARSE_SLOWLY(name, sample) \
-    while (0) { \
-      static_cast<void>(name); \
-      static_cast<void>(sample); \
-    }
-
-#endif  // NDEBUG
-
 class HistogramSamples;
 
 class BASE_EXPORT_PRIVATE SparseHistogram : public HistogramBase {