Allow UmaHistogramEnumeration to be used with enum classes.

base/metrics/histogram_functions.h

Index: base/metrics/histogram_functions.h
diff --git a/base/metrics/histogram_functions.h b/base/metrics/histogram_functions.h
index 58fc30173c6ea17480175440202c384b96661261..5960aca657497357e7146aff8b0e5997b9d356f6 100644
--- a/base/metrics/histogram_functions.h
+++ b/base/metrics/histogram_functions.h
@@ -43,7 +43,10 @@ template <typename T>
 void UmaHistogramEnumeration(const std::string& name, T sample, T max) {
   static_assert(std::is_enum<T>::value,
                 "Non enum passed to UmaHistogramEnumeration");
-  return UmaHistogramExactLinear(name, static_cast<int>(sample), max);
+  DCHECK_LE(static_cast<uintmax_t>(max), static_cast<uintmax_t>(INT_MAX));
+  DCHECK_LE(static_cast<uintmax_t>(sample), static_cast<uintmax_t>(max));
+  return UmaHistogramExactLinear(name, static_cast<int>(sample),
+                                 static_cast<int>(max));
 }
 
 // For adding boolean sample to histogram.