remove DISALLOW_COPY_AND_ASSIGN from base/metrics/*

A few cpp lint fixes, no functional changes.

Bug: 1010217
Change-Id: Ia08f6fe65e937d0155e3b25184d061d7bd736f76
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2412748Reviewed-by: Ilya Sherman <isherman@chromium.org>
Commit-Queue: David Bienvenu <davidbienvenu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#807615}

base/metrics/dummy_histogram.cc

@@ -18,8 +18,10 @@ namespace {
 // Helper classes for DummyHistogram.
 class DummySampleCountIterator : public SampleCountIterator {
  public:
-  DummySampleCountIterator() {}
-  ~DummySampleCountIterator() override {}
+  DummySampleCountIterator() = default;
+  DummySampleCountIterator(const DummySampleCountIterator&) = delete;
+  DummySampleCountIterator& operator=(const DummySampleCountIterator&) = delete;
+  ~DummySampleCountIterator() override = default;
 
   // SampleCountIterator:
   bool Done() const override { return true; }
@@ -29,14 +31,13 @@ class DummySampleCountIterator : public SampleCountIterator {
            HistogramBase::Count* count) const override {
     NOTREACHED();
   }
-
- private:
-  DISALLOW_COPY_AND_ASSIGN(DummySampleCountIterator);
 };
 
 class DummyHistogramSamples : public HistogramSamples {
  public:
-  explicit DummyHistogramSamples() : HistogramSamples(0, new LocalMetadata()) {}
+  DummyHistogramSamples() : HistogramSamples(0, new LocalMetadata()) {}
+  DummyHistogramSamples(const DummyHistogramSamples&) = delete;
+  DummyHistogramSamples& operator=(const DummyHistogramSamples&) = delete;
   ~DummyHistogramSamples() override {
     delete static_cast<LocalMetadata*>(meta());
   }
@@ -56,9 +57,6 @@ class DummyHistogramSamples : public HistogramSamples {
   bool AddSubtractImpl(SampleCountIterator* iter, Operator op) override {
     return true;
   }
-
- private:
-  DISALLOW_COPY_AND_ASSIGN(DummyHistogramSamples);
 };
 
 }  // namespace

base/metrics/field_trial.h

@@ -67,7 +67,6 @@
 #include "base/command_line.h"
 #include "base/feature_list.h"
 #include "base/gtest_prod_util.h"
-#include "base/macros.h"
 #include "base/memory/read_only_shared_memory_region.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/shared_memory_mapping.h"
@@ -185,6 +184,9 @@ class BASE_EXPORT FieldTrial : public RefCounted<FieldTrial> {
   // assignment (and hence is not yet participating in the trial).
   static const int kNotFinalized;
 
+  FieldTrial(const FieldTrial&) = delete;
+  FieldTrial& operator=(const FieldTrial&) = delete;
+
   // Disables this trial, meaning it always determines the default group
   // has been selected. May be called immediately after construction, or
   // at any time after initialization (should not be interleaved with
@@ -290,6 +292,7 @@ class BASE_EXPORT FieldTrial : public RefCounted<FieldTrial> {
              Probability total_probability,
              const std::string& default_group_name,
              double entropy_value);
+
   virtual ~FieldTrial();
 
   // Return the default group name of the FieldTrial.
@@ -380,8 +383,6 @@ class BASE_EXPORT FieldTrial : public RefCounted<FieldTrial> {
   // When benchmarking is enabled, field trials all revert to the 'default'
   // group.
   static bool enable_benchmarking_;
-
-  DISALLOW_COPY_AND_ASSIGN(FieldTrial);
 };
 
 //------------------------------------------------------------------------------
@@ -416,6 +417,8 @@ class BASE_EXPORT FieldTrialList {
   // |entropy_provider|.
   explicit FieldTrialList(
       std::unique_ptr<const FieldTrial::EntropyProvider> entropy_provider);
+  FieldTrialList(const FieldTrialList&) = delete;
+  FieldTrialList& operator=(const FieldTrialList&) = delete;
 
   // Destructor Release()'s references to all registered FieldTrial instances.
   ~FieldTrialList();
@@ -796,8 +799,6 @@ class BASE_EXPORT FieldTrialList {
 
   // Tracks whether CreateTrialsFromCommandLine() has been called.
   bool create_trials_from_command_line_called_ = false;
-
-  DISALLOW_COPY_AND_ASSIGN(FieldTrialList);
 };
 
 }  // namespace base

base/metrics/field_trial_unittest.cc

@@ -63,12 +63,14 @@ class TestFieldTrialObserver : public FieldTrialList::Observer {
     SYNCHRONOUS,
   };
 
-  TestFieldTrialObserver(Type type) : type_(type) {
+  explicit TestFieldTrialObserver(Type type) : type_(type) {
     if (type == SYNCHRONOUS)
       FieldTrialList::SetSynchronousObserver(this);
     else
       FieldTrialList::AddObserver(this);
   }
+  TestFieldTrialObserver(const TestFieldTrialObserver&) = delete;
+  TestFieldTrialObserver& operator=(const TestFieldTrialObserver&) = delete;
 
   ~TestFieldTrialObserver() override {
     if (type_ == SYNCHRONOUS)
@@ -90,8 +92,6 @@ class TestFieldTrialObserver : public FieldTrialList::Observer {
   const Type type_;
   std::string trial_name_;
   std::string group_name_;
-
-  DISALLOW_COPY_AND_ASSIGN(TestFieldTrialObserver);
 };
 
 std::string MockEscapeQueryParamValue(const std::string& input) {
@@ -103,6 +103,8 @@ std::string MockEscapeQueryParamValue(const std::string& input) {
 class FieldTrialTest : public ::testing::Test {
  public:
   FieldTrialTest() : trial_list_(nullptr) {}
+  FieldTrialTest(const FieldTrialTest&) = delete;
+  FieldTrialTest& operator=(const FieldTrialTest&) = delete;
 
  private:
   test::TaskEnvironment task_environment_;
@@ -110,8 +112,6 @@ class FieldTrialTest : public ::testing::Test {
   // tests it's cleaner to start from scratch.
   test::ScopedFieldTrialListResetter trial_list_resetter_;
   FieldTrialList trial_list_;
-
-  DISALLOW_COPY_AND_ASSIGN(FieldTrialTest);
 };
 
 // Test registration, and also check that destructors are called for trials.

base/metrics/histogram_base_unittest.cc

@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+#include <limits>
 #include <vector>
 
 #include "base/metrics/histogram.h"
@@ -15,15 +16,18 @@
 namespace base {
 
 class HistogramBaseTest : public testing::Test {
- protected:
+ public:
   HistogramBaseTest() {
     // Each test will have a clean state (no Histogram / BucketRanges
     // registered).
     ResetStatisticsRecorder();
   }
 
+  HistogramBaseTest(const HistogramBaseTest&) = delete;
+  HistogramBaseTest& operator=(const HistogramBaseTest&) = delete;
   ~HistogramBaseTest() override = default;
 
+ protected:
   void ResetStatisticsRecorder() {
     // It is necessary to fully destruct any existing StatisticsRecorder
     // before creating a new one.
@@ -33,8 +37,6 @@ class HistogramBaseTest : public testing::Test {
 
  private:
   std::unique_ptr<StatisticsRecorder> statistics_recorder_;
-
-  DISALLOW_COPY_AND_ASSIGN(HistogramBaseTest);
 };
 
 TEST_F(HistogramBaseTest, DeserializeHistogram) {

base/metrics/histogram_flattener.h

@@ -8,7 +8,6 @@
 #include <map>
 #include <string>
 
-#include "base/macros.h"
 #include "base/metrics/histogram.h"
 
 namespace base {
@@ -19,6 +18,8 @@ class HistogramSamples;
 // handles the logistics of gathering up available histograms for recording.
 class BASE_EXPORT HistogramFlattener {
  public:
+  HistogramFlattener(const HistogramFlattener&) = delete;
+  HistogramFlattener& operator=(const HistogramFlattener&) = delete;
   virtual ~HistogramFlattener() = default;
 
   virtual void RecordDelta(const HistogramBase& histogram,
@@ -26,9 +27,6 @@ class BASE_EXPORT HistogramFlattener {
 
  protected:
   HistogramFlattener() = default;
-
- private:
-  DISALLOW_COPY_AND_ASSIGN(HistogramFlattener);
 };
 
 }  // namespace base

base/metrics/histogram_samples.h

@@ -12,7 +12,6 @@
 #include <memory>
 
 #include "base/atomicops.h"
-#include "base/macros.h"
 #include "base/metrics/histogram_base.h"
 
 namespace base {
@@ -129,6 +128,8 @@ class BASE_EXPORT HistogramSamples {
   };
 
   HistogramSamples(uint64_t id, Metadata* meta);
+  HistogramSamples(const HistogramSamples&) = delete;
+  HistogramSamples& operator=(const HistogramSamples&) = delete;
   virtual ~HistogramSamples();
 
   virtual void Accumulate(HistogramBase::Sample value,
@@ -203,8 +204,6 @@ class BASE_EXPORT HistogramSamples {
   // external storage in which case HistogramSamples class cannot take ownership
   // of Metadata*.
   Metadata* meta_;
-
-  DISALLOW_COPY_AND_ASSIGN(HistogramSamples);
 };
 
 class BASE_EXPORT SampleCountIterator {

base/metrics/histogram_snapshot_manager.cc

@@ -21,16 +21,16 @@ namespace {
 // an error if the flag is already set.
 class MakeActive {
  public:
-  MakeActive(std::atomic<bool>* is_active) : is_active_(is_active) {
+  explicit MakeActive(std::atomic<bool>* is_active) : is_active_(is_active) {
     bool was_active = is_active_->exchange(true, std::memory_order_relaxed);
     CHECK(!was_active);
   }
+  MakeActive(const MakeActive&) = delete;
+  MakeActive& operator=(const MakeActive&) = delete;
   ~MakeActive() { is_active_->store(false, std::memory_order_relaxed); }
 
  private:
   std::atomic<bool>* is_active_;
-
-  DISALLOW_COPY_AND_ASSIGN(MakeActive);
 };
 
 }  // namespace

base/metrics/sample_vector.h

@@ -17,7 +17,6 @@
 #include "base/atomicops.h"
 #include "base/compiler_specific.h"
 #include "base/gtest_prod_util.h"
-#include "base/macros.h"
 #include "base/metrics/bucket_ranges.h"
 #include "base/metrics/histogram_base.h"
 #include "base/metrics/histogram_samples.h"
@@ -32,6 +31,8 @@ class BASE_EXPORT SampleVectorBase : public HistogramSamples {
   SampleVectorBase(uint64_t id,
                    Metadata* meta,
                    const BucketRanges* bucket_ranges);
+  SampleVectorBase(const SampleVectorBase&) = delete;
+  SampleVectorBase& operator=(const SampleVectorBase&) = delete;
   ~SampleVectorBase() override;
 
   // HistogramSamples:
@@ -107,8 +108,6 @@ class BASE_EXPORT SampleVectorBase : public HistogramSamples {
 
   // Shares the same BucketRanges with Histogram object.
   const BucketRanges* const bucket_ranges_;
-
-  DISALLOW_COPY_AND_ASSIGN(SampleVectorBase);
 };
 
 // A sample vector that uses local memory for the counts array.
@@ -116,6 +115,8 @@ class BASE_EXPORT SampleVector : public SampleVectorBase {
  public:
   explicit SampleVector(const BucketRanges* bucket_ranges);
   SampleVector(uint64_t id, const BucketRanges* bucket_ranges);
+  SampleVector(const SampleVector&) = delete;
+  SampleVector& operator=(const SampleVector&) = delete;
   ~SampleVector() override;
 
  private:
@@ -125,8 +126,6 @@ class BASE_EXPORT SampleVector : public SampleVectorBase {
 
   // Simple local storage for counts.
   mutable std::vector<HistogramBase::AtomicCount> local_counts_;
-
-  DISALLOW_COPY_AND_ASSIGN(SampleVector);
 };
 
 // A sample vector that uses persistent memory for the counts array.
@@ -136,6 +135,8 @@ class BASE_EXPORT PersistentSampleVector : public SampleVectorBase {
                          const BucketRanges* bucket_ranges,
                          Metadata* meta,
                          const DelayedPersistentAllocation& counts);
+  PersistentSampleVector(const PersistentSampleVector&) = delete;
+  PersistentSampleVector& operator=(const PersistentSampleVector&) = delete;
   ~PersistentSampleVector() override;
 
  private:
@@ -145,8 +146,6 @@ class BASE_EXPORT PersistentSampleVector : public SampleVectorBase {
 
   // Persistent storage for counts.
   DelayedPersistentAllocation persistent_counts_;
-
-  DISALLOW_COPY_AND_ASSIGN(PersistentSampleVector);
 };
 
 // An iterator for sample vectors. This could be defined privately in the .cc

base/metrics/single_sample_metrics.h

@@ -5,10 +5,10 @@
 #ifndef BASE_METRICS_SINGLE_SAMPLE_METRICS_H_
 #define BASE_METRICS_SINGLE_SAMPLE_METRICS_H_
 
+#include <memory>
 #include <string>
 
 #include "base/base_export.h"
-#include "base/macros.h"
 #include "base/metrics/histogram_base.h"
 
 namespace base {
@@ -64,6 +64,10 @@ class BASE_EXPORT DefaultSingleSampleMetricsFactory
     : public SingleSampleMetricsFactory {
  public:
   DefaultSingleSampleMetricsFactory() = default;
+  DefaultSingleSampleMetricsFactory(const DefaultSingleSampleMetricsFactory&) =
+      delete;
+  DefaultSingleSampleMetricsFactory& operator=(
+      const DefaultSingleSampleMetricsFactory&) = delete;
   ~DefaultSingleSampleMetricsFactory() override = default;
 
   // SingleSampleMetricsFactory:
@@ -72,9 +76,6 @@ class BASE_EXPORT DefaultSingleSampleMetricsFactory
       HistogramBase::Sample min,
       HistogramBase::Sample max,
       uint32_t bucket_count) override;
-
- private:
-  DISALLOW_COPY_AND_ASSIGN(DefaultSingleSampleMetricsFactory);
 };
 
 class BASE_EXPORT DefaultSingleSampleMetric : public SingleSampleMetric {

base/metrics/sparse_histogram_unittest.cc

@@ -6,6 +6,7 @@
 
 #include <memory>
 #include <string>
+#include <vector>
 
 #include "base/logging.h"
 #include "base/metrics/histogram_base.h"
@@ -29,11 +30,14 @@ namespace base {
 // for histogram allocation. False will allocate histograms from the process
 // heap.
 class SparseHistogramTest : public testing::TestWithParam<bool> {
+ public:
+  SparseHistogramTest() : use_persistent_histogram_allocator_(GetParam()) {}
+  SparseHistogramTest(const SparseHistogramTest&) = delete;
+  SparseHistogramTest& operator=(const SparseHistogramTest&) = delete;
+
  protected:
   const int32_t kAllocatorMemorySize = 8 << 20;  // 8 MiB
 
-  SparseHistogramTest() : use_persistent_histogram_allocator_(GetParam()) {}
-
   void SetUp() override {
     if (use_persistent_histogram_allocator_)
       CreatePersistentMemoryAllocator();
@@ -91,9 +95,6 @@ class SparseHistogramTest : public testing::TestWithParam<bool> {
 
   std::unique_ptr<StatisticsRecorder> statistics_recorder_;
   PersistentMemoryAllocator* allocator_ = nullptr;
-
- private:
-  DISALLOW_COPY_AND_ASSIGN(SparseHistogramTest);
 };
 
 // Run all HistogramTest cases with both heap and persistent memory.

base/metrics/statistics_recorder_unittest.cc

@@ -30,14 +30,13 @@ namespace {
 // contained (i.e., do not affect other unit tests).
 class LogStateSaver {
  public:
-  LogStateSaver() : old_min_log_level_(logging::GetMinLogLevel()) {}
-
+  LogStateSaver() = default;
+  LogStateSaver(const LogStateSaver&) = delete;
+  LogStateSaver& operator=(const LogStateSaver&) = delete;
   ~LogStateSaver() { logging::SetMinLogLevel(old_min_log_level_); }
 
  private:
-  int old_min_log_level_;
-
-  DISALLOW_COPY_AND_ASSIGN(LogStateSaver);
+  int old_min_log_level_ = logging::GetMinLogLevel();
 };
 
 // Test implementation of RecordHistogramChecker interface.
@@ -60,6 +59,10 @@ using testing::SizeIs;
 using testing::UnorderedElementsAre;
 
 class StatisticsRecorderTest : public testing::TestWithParam<bool> {
+ public:
+  StatisticsRecorderTest(const StatisticsRecorderTest&) = delete;
+  StatisticsRecorderTest& operator=(const StatisticsRecorderTest&) = delete;
+
  protected:
   const int32_t kAllocatorMemorySize = 64 << 10;  // 64 KiB
 
@@ -122,8 +125,6 @@ class StatisticsRecorderTest : public testing::TestWithParam<bool> {
 
  private:
   LogStateSaver log_state_saver_;
-
-  DISALLOW_COPY_AND_ASSIGN(StatisticsRecorderTest);
 };
 
 // Run all HistogramTest cases with both heap and persistent memory.
@@ -701,6 +702,8 @@ class TestHistogramProvider : public StatisticsRecorder::HistogramProvider {
       : allocator_(std::move(allocator)) {
     StatisticsRecorder::RegisterHistogramProvider(weak_factory_.GetWeakPtr());
   }
+  TestHistogramProvider(const TestHistogramProvider&) = delete;
+  TestHistogramProvider& operator=(const TestHistogramProvider&) = delete;
 
   void MergeHistogramDeltas() override {
     PersistentHistogramAllocator::Iterator hist_iter(allocator_.get());
@@ -715,8 +718,6 @@ class TestHistogramProvider : public StatisticsRecorder::HistogramProvider {
  private:
   std::unique_ptr<PersistentHistogramAllocator> allocator_;
   WeakPtrFactory<TestHistogramProvider> weak_factory_{this};
-
-  DISALLOW_COPY_AND_ASSIGN(TestHistogramProvider);
 };
 
 TEST_P(StatisticsRecorderTest, ImportHistogramsTest) {