Revert of Collect information about failing histogram factory calls.

base/metrics/metrics_hashes.cc

 // Copyright 2014 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.
 
 #include "base/metrics/metrics_hashes.h"
 
-#include "base/debug/alias.h"
 #include "base/logging.h"
 #include "base/md5.h"
 #include "base/sys_byteorder.h"
 
 namespace base {
 
 namespace {
 
 // Converts the 8-byte prefix of an MD5 hash into a uint64_t value.
 inline uint64_t DigestToUInt64(const base::MD5Digest& digest) {
   uint64_t value;
-  CHECK_GE(sizeof(digest.a), sizeof(value));
+  DCHECK_GE(sizeof(digest.a), sizeof(value));
   memcpy(&value, digest.a, sizeof(value));
-  uint64_t hash = base::NetToHost64(value);
-  CHECK_NE(0U, hash);
-  base::debug::Alias(&hash);
-  base::debug::Alias(&value);
-  base::debug::Alias(&digest);
-  return hash;
+  return base::NetToHost64(value);
 }
 
 }  // namespace
 
 uint64_t HashMetricName(base::StringPiece name) {
   base::MD5Digest digest;
   base::MD5Sum(name.data(), name.size(), &digest);
   return DigestToUInt64(digest);
 }
 
 }  // namespace metrics