Histograms - Make DCHECK More Strict

Change-Id: Ifb8cc02dc6d7cd3379316e52f51b6b3303451b03
Reviewed-on: https://chromium-review.googlesource.com/1057996Reviewed-by: Steven Holte <holte@chromium.org>
Commit-Queue: Mark Pearson <mpearson@chromium.org>
Cr-Commit-Position: refs/heads/master@{#558777}

base/metrics/histogram_functions.h

@@ -54,7 +54,7 @@ void UmaHistogramEnumeration(const std::string& name, T sample, T enum_size) {
   static_assert(std::is_enum<T>::value,
                 "Non enum passed to UmaHistogramEnumeration");
   DCHECK_LE(static_cast<uintmax_t>(enum_size), static_cast<uintmax_t>(INT_MAX));
-  DCHECK_LE(static_cast<uintmax_t>(sample), static_cast<uintmax_t>(enum_size));
+  DCHECK_LT(static_cast<uintmax_t>(sample), static_cast<uintmax_t>(enum_size));
   return UmaHistogramExactLinear(name, static_cast<int>(sample),
                                  static_cast<int>(enum_size));
 }