Fix vector indexing bug in SerializationUtilsTest.WriteReadTest

components/metrics/serialization/serialization_utils_unittest.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 "components/metrics/serialization/serialization_utils.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include "base/files/file_util.h"
@@ skipping 136 matching lines @@
       MetricSample::UserActionSample("myaction");
 
   SerializationUtils::WriteMetricToFile(*hist.get(), filename);
   SerializationUtils::WriteMetricToFile(*crash.get(), filename);
   SerializationUtils::WriteMetricToFile(*lhist.get(), filename);
   SerializationUtils::WriteMetricToFile(*shist.get(), filename);
   SerializationUtils::WriteMetricToFile(*action.get(), filename);
   ScopedVector<MetricSample> vect;
   SerializationUtils::ReadAndTruncateMetricsFromFile(filename, &vect);
   ASSERT_EQ(vect.size(), size_t(5));
-  for (int i = 0; i < 5; i++) {
-    ASSERT_TRUE(vect[0] != NULL);
+  for (MetricSample* sample : vect) {
+    ASSERT_NE(nullptr, sample);
   }
   EXPECT_TRUE(hist->IsEqual(*vect[0]));
   EXPECT_TRUE(crash->IsEqual(*vect[1]));
   EXPECT_TRUE(lhist->IsEqual(*vect[2]));
   EXPECT_TRUE(shist->IsEqual(*vect[3]));
   EXPECT_TRUE(action->IsEqual(*vect[4]));
 
   int64_t size = 0;
   ASSERT_TRUE(base::GetFileSize(filepath, &size));
   ASSERT_EQ(0, size);
 }
 
 }  // namespace
 }  // namespace metrics