Change EXPECT/ASSERT_DCHECK_DEATH macro to not expose the |regex| parameter.

base/metrics/histogram_unittest.cc

 // Copyright (c) 2012 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/histogram.h"
 
 #include <limits.h>
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 719 matching lines @@
   const BucketRanges* ranges = custom_histogram->bucket_ranges();
   ASSERT_EQ(3u, ranges->size());
   EXPECT_EQ(0, ranges->range(0));
   EXPECT_EQ(5, ranges->range(1));
   EXPECT_EQ(HistogramBase::kSampleType_MAX, ranges->range(2));
 
   // CustomHistogram does not accepts kSampleType_MAX as range.
   custom_ranges.push_back(HistogramBase::kSampleType_MAX);
   EXPECT_DCHECK_DEATH(
       CustomHistogram::FactoryGet("BadRangesCustom2", custom_ranges,
-                                  HistogramBase::kNoFlags),
-      "");
+                                  HistogramBase::kNoFlags));
 
   // CustomHistogram needs at least 1 valid range.
   custom_ranges.clear();
   custom_ranges.push_back(0);
   EXPECT_DCHECK_DEATH(
       CustomHistogram::FactoryGet("BadRangesCustom3", custom_ranges,
-                                  HistogramBase::kNoFlags),
-      "");
+                                  HistogramBase::kNoFlags));
 }
 
 }  // namespace base