Run clang-tidy modernize-use-equals-{delete,default} on //base

See the bugs and cxx post for justification and details:
https://groups.google.com/a/chromium.org/forum/#!topic/cxx/RkOHzIK6Tq8

This change was done using clang-tidy as described here:
https://chromium.googlesource.com/chromium/src/+/lkcr/docs/clang_tidy.md

In some cases the the tool leaves behind a string of commas where it
replaced a member initializer list
(https://bugs.llvm.org/show_bug.cgi?id=35051). They were cleaned up with:
  git diff --name-only | \
    xargs sed -E -i 's/(^\s*|\)\s*):[ ,]*= default/\1 = default/'

BUG=778959,778957

Change-Id: I95a3f3dae4796e4a7beb77793a6101f433a2c649
Reviewed-on: https://chromium-review.googlesource.com/789718
Reviewed-by: Daniel Cheng <dcheng@chromium.org>
Commit-Queue: Chris Watkins <watk@chromium.org>
Cr-Commit-Position: refs/heads/master@{#520033}

base/allocator/partition_allocator/partition_alloc_unittest.cc

@@ -103,9 +103,9 @@ const char* type_name = nullptr;
 
 class PartitionAllocTest : public testing::Test {
  protected:
-  PartitionAllocTest() {}
+  PartitionAllocTest() = default;
 
-  ~PartitionAllocTest() override {}
+  ~PartitionAllocTest() override = default;
 
   void SetUp() override {
     allocator.init();

base/bind_unittest.cc

@@ -31,7 +31,7 @@ class IncompleteType;
 
 class NoRef {
  public:
-  NoRef() {}
+  NoRef() = default;
 
   MOCK_METHOD0(VoidMethod0, void());
   MOCK_CONST_METHOD0(VoidConstMethod0, void());
@@ -49,7 +49,7 @@ class NoRef {
 
 class HasRef : public NoRef {
  public:
-  HasRef() {}
+  HasRef() = default;
 
   MOCK_CONST_METHOD0(AddRef, void());
   MOCK_CONST_METHOD0(Release, bool());
@@ -61,7 +61,7 @@ class HasRef : public NoRef {
 
 class HasRefPrivateDtor : public HasRef {
  private:
-  ~HasRefPrivateDtor() {}
+  ~HasRefPrivateDtor() = default;
 };
 
 static const int kParentValue = 1;
@@ -196,11 +196,8 @@ class CopyCounter {
  public:
   CopyCounter(int* copies, int* assigns)
       : counter_(copies, assigns, nullptr, nullptr) {}
-  CopyCounter(const CopyCounter& other) : counter_(other.counter_) {}
-  CopyCounter& operator=(const CopyCounter& other) {
-    counter_ = other.counter_;
-    return *this;
-  }
+  CopyCounter(const CopyCounter& other) = default;
+  CopyCounter& operator=(const CopyCounter& other) = default;
 
   explicit CopyCounter(const DerivedCopyMoveCounter& other) : counter_(other) {}
 
@@ -321,8 +318,7 @@ class BindTest : public ::testing::Test {
     static_func_mock_ptr = &static_func_mock_;
   }
 
-  virtual ~BindTest() {
-  }
+  virtual ~BindTest() = default;
 
   static void VoidFunc0() {
     static_func_mock_ptr->VoidMethod0();

base/callback_helpers.cc

@@ -6,7 +6,7 @@
 
 namespace base {
 
-ScopedClosureRunner::ScopedClosureRunner() {}
+ScopedClosureRunner::ScopedClosureRunner() = default;
 
 ScopedClosureRunner::ScopedClosureRunner(OnceClosure closure)
     : closure_(std::move(closure)) {}

base/callback_internal.cc

@@ -71,7 +71,7 @@ CallbackBase::CallbackBase(BindStateBase* bind_state)
   DCHECK(!bind_state_.get() || bind_state_->HasOneRef());
 }
 
-CallbackBase::~CallbackBase() {}
+CallbackBase::~CallbackBase() = default;
 
 CallbackBaseCopyable::CallbackBaseCopyable(const CallbackBaseCopyable& c)
     : CallbackBase(nullptr) {

base/callback_unittest.cc

@@ -25,7 +25,7 @@ struct FakeBindState : internal::BindStateBase {
   FakeBindState() : BindStateBase(&NopInvokeFunc, &Destroy, &IsCancelled) {}
 
  private:
-  ~FakeBindState() {}
+  ~FakeBindState() = default;
   static void Destroy(const internal::BindStateBase* self) {
     delete static_cast<const FakeBindState*>(self);
   }
@@ -41,7 +41,7 @@ class CallbackTest : public ::testing::Test {
   CallbackTest()
       : callback_a_(new FakeBindState()), callback_b_(new FakeBindState()) {}
 
-  ~CallbackTest() override {}
+  ~CallbackTest() override = default;
 
  protected:
   Callback<void()> callback_a_;

base/cancelable_callback_unittest.cc

@@ -23,7 +23,8 @@ namespace {
 class TestRefCounted : public RefCountedThreadSafe<TestRefCounted> {
  private:
   friend class RefCountedThreadSafe<TestRefCounted>;
-  ~TestRefCounted() {};
+  ~TestRefCounted() = default;
+  ;
 };
 
 void Increment(int* count) { (*count)++; }

base/command_line.cc

@@ -174,21 +174,11 @@ CommandLine::CommandLine(const StringVector& argv)
   InitFromArgv(argv);
 }
 
-CommandLine::CommandLine(const CommandLine& other)
-    : argv_(other.argv_),
-      switches_(other.switches_),
-      begin_args_(other.begin_args_) {
-}
+CommandLine::CommandLine(const CommandLine& other) = default;
 
-CommandLine& CommandLine::operator=(const CommandLine& other) {
-  argv_ = other.argv_;
-  switches_ = other.switches_;
-  begin_args_ = other.begin_args_;
-  return *this;
-}
+CommandLine& CommandLine::operator=(const CommandLine& other) = default;
 
-CommandLine::~CommandLine() {
-}
+CommandLine::~CommandLine() = default;
 
 #if defined(OS_WIN)
 // static

base/containers/linked_list_unittest.cc

@@ -28,7 +28,7 @@ class MultipleInheritanceNodeBase {
 class MultipleInheritanceNode : public MultipleInheritanceNodeBase,
                                 public LinkNode<MultipleInheritanceNode> {
  public:
-  MultipleInheritanceNode() {}
+  MultipleInheritanceNode() = default;
 };
 
 // Checks that when iterating |list| (either from head to tail, or from

base/containers/small_map_unittest.cc

@@ -443,7 +443,7 @@ namespace {
 
 class unordered_map_add_item : public std::unordered_map<int, int> {
  public:
-  unordered_map_add_item() {}
+  unordered_map_add_item() = default;
   explicit unordered_map_add_item(const std::pair<int, int>& item) {
     insert(item);
   }

base/containers/stack_container_unittest.cc

@@ -107,7 +107,7 @@ template <size_t alignment>
 class AlignedData {
  public:
   AlignedData() { memset(data_, 0, alignment); }
-  ~AlignedData() {}
+  ~AlignedData() = default;
   alignas(alignment) char data_[alignment];
 };
 

base/debug/activity_analyzer.cc

@@ -41,8 +41,8 @@ void LogAnalyzerCreationError(AnalyzerCreationError error) {
 
 }  // namespace
 
-ThreadActivityAnalyzer::Snapshot::Snapshot() {}
-ThreadActivityAnalyzer::Snapshot::~Snapshot() {}
+ThreadActivityAnalyzer::Snapshot::Snapshot() = default;
+ThreadActivityAnalyzer::Snapshot::~Snapshot() = default;
 
 ThreadActivityAnalyzer::ThreadActivityAnalyzer(
     const ThreadActivityTracker& tracker)
@@ -60,7 +60,7 @@ ThreadActivityAnalyzer::ThreadActivityAnalyzer(
                                  PersistentMemoryAllocator::kSizeAny),
                              allocator->GetAllocSize(reference)) {}
 
-ThreadActivityAnalyzer::~ThreadActivityAnalyzer() {}
+ThreadActivityAnalyzer::~ThreadActivityAnalyzer() = default;
 
 void ThreadActivityAnalyzer::AddGlobalInformation(
     GlobalActivityAnalyzer* global) {
@@ -87,7 +87,7 @@ GlobalActivityAnalyzer::GlobalActivityAnalyzer(
   DCHECK(allocator_);
 }
 
-GlobalActivityAnalyzer::~GlobalActivityAnalyzer() {}
+GlobalActivityAnalyzer::~GlobalActivityAnalyzer() = default;
 
 // static
 std::unique_ptr<GlobalActivityAnalyzer>
@@ -298,12 +298,12 @@ bool GlobalActivityAnalyzer::IsDataComplete() const {
   return !allocator_->IsFull();
 }
 
-GlobalActivityAnalyzer::UserDataSnapshot::UserDataSnapshot() {}
+GlobalActivityAnalyzer::UserDataSnapshot::UserDataSnapshot() = default;
 GlobalActivityAnalyzer::UserDataSnapshot::UserDataSnapshot(
     const UserDataSnapshot& rhs) = default;
 GlobalActivityAnalyzer::UserDataSnapshot::UserDataSnapshot(
     UserDataSnapshot&& rhs) = default;
-GlobalActivityAnalyzer::UserDataSnapshot::~UserDataSnapshot() {}
+GlobalActivityAnalyzer::UserDataSnapshot::~UserDataSnapshot() = default;
 
 void GlobalActivityAnalyzer::PrepareAllAnalyzers() {
   // Record the time when analysis started.

base/debug/activity_analyzer_unittest.cc

@@ -37,7 +37,7 @@ class TestActivityTracker : public ThreadActivityTracker {
       : ThreadActivityTracker(memset(memory.get(), 0, mem_size), mem_size),
         mem_segment_(std::move(memory)) {}
 
-  ~TestActivityTracker() override {}
+  ~TestActivityTracker() override = default;
 
  private:
   std::unique_ptr<char[]> mem_segment_;
@@ -51,7 +51,7 @@ class ActivityAnalyzerTest : public testing::Test {
   const int kMemorySize = 1 << 20;  // 1MiB
   const int kStackSize  = 1 << 10;  // 1KiB
 
-  ActivityAnalyzerTest() {}
+  ActivityAnalyzerTest() = default;
 
   ~ActivityAnalyzerTest() override {
     GlobalActivityTracker* global_tracker = GlobalActivityTracker::Get();
@@ -119,7 +119,7 @@ class SimpleActivityThread : public SimpleThread {
         exit_(false),
         exit_condition_(&lock_) {}
 
-  ~SimpleActivityThread() override {}
+  ~SimpleActivityThread() override = default;
 
   void Run() override {
     ThreadActivityTracker::ActivityId id =

base/debug/activity_tracker.cc

@@ -120,8 +120,8 @@ Time WallTimeFromTickTime(int64_t ticks_start, int64_t ticks, Time time_start) {
 
 }  // namespace
 
-OwningProcess::OwningProcess() {}
-OwningProcess::~OwningProcess() {}
+OwningProcess::OwningProcess() = default;
+OwningProcess::~OwningProcess() = default;
 
 void OwningProcess::Release_Initialize(int64_t pid) {
   uint32_t old_id = data_id.load(std::memory_order_acquire);
@@ -185,7 +185,7 @@ ActivityTrackerMemoryAllocator::ActivityTrackerMemoryAllocator(
   DCHECK(allocator);
 }
 
-ActivityTrackerMemoryAllocator::~ActivityTrackerMemoryAllocator() {}
+ActivityTrackerMemoryAllocator::~ActivityTrackerMemoryAllocator() = default;
 
 ActivityTrackerMemoryAllocator::Reference
 ActivityTrackerMemoryAllocator::GetObjectReference() {
@@ -276,9 +276,9 @@ void Activity::FillFrom(Activity* activity,
 #endif
 }
 
-ActivityUserData::TypedValue::TypedValue() {}
+ActivityUserData::TypedValue::TypedValue() = default;
 ActivityUserData::TypedValue::TypedValue(const TypedValue& other) = default;
-ActivityUserData::TypedValue::~TypedValue() {}
+ActivityUserData::TypedValue::~TypedValue() = default;
 
 StringPiece ActivityUserData::TypedValue::Get() const {
   DCHECK_EQ(RAW_VALUE, type_);
@@ -323,13 +323,13 @@ StringPiece ActivityUserData::TypedValue::GetStringReference() const {
 // These are required because std::atomic is (currently) not a POD type and
 // thus clang requires explicit out-of-line constructors and destructors even
 // when they do nothing.
-ActivityUserData::ValueInfo::ValueInfo() {}
+ActivityUserData::ValueInfo::ValueInfo() = default;
 ActivityUserData::ValueInfo::ValueInfo(ValueInfo&&) = default;
-ActivityUserData::ValueInfo::~ValueInfo() {}
-ActivityUserData::MemoryHeader::MemoryHeader() {}
-ActivityUserData::MemoryHeader::~MemoryHeader() {}
-ActivityUserData::FieldHeader::FieldHeader() {}
-ActivityUserData::FieldHeader::~FieldHeader() {}
+ActivityUserData::ValueInfo::~ValueInfo() = default;
+ActivityUserData::MemoryHeader::MemoryHeader() = default;
+ActivityUserData::MemoryHeader::~MemoryHeader() = default;
+ActivityUserData::FieldHeader::FieldHeader() = default;
+ActivityUserData::FieldHeader::~FieldHeader() = default;
 
 ActivityUserData::ActivityUserData() : ActivityUserData(nullptr, 0, -1) {}
 
@@ -362,7 +362,7 @@ ActivityUserData::ActivityUserData(void* memory, size_t size, int64_t pid)
   ImportExistingData();
 }
 
-ActivityUserData::~ActivityUserData() {}
+ActivityUserData::~ActivityUserData() = default;
 
 bool ActivityUserData::CreateSnapshot(Snapshot* output_snapshot) const {
   DCHECK(output_snapshot);
@@ -655,8 +655,8 @@ struct ThreadActivityTracker::Header {
   char thread_name[32];
 };
 
-ThreadActivityTracker::Snapshot::Snapshot() {}
-ThreadActivityTracker::Snapshot::~Snapshot() {}
+ThreadActivityTracker::Snapshot::Snapshot() = default;
+ThreadActivityTracker::Snapshot::~Snapshot() = default;
 
 ThreadActivityTracker::ScopedActivity::ScopedActivity(
     ThreadActivityTracker* tracker,
@@ -758,7 +758,7 @@ ThreadActivityTracker::ThreadActivityTracker(void* base, size_t size)
   }
 }
 
-ThreadActivityTracker::~ThreadActivityTracker() {}
+ThreadActivityTracker::~ThreadActivityTracker() = default;
 
 ThreadActivityTracker::ActivityId ThreadActivityTracker::PushActivity(
     const void* program_counter,
@@ -1082,18 +1082,18 @@ ThreadActivityTracker::CreateUserDataForActivity(
 // of std::atomic because the latter can create global ctors and dtors.
 subtle::AtomicWord GlobalActivityTracker::g_tracker_ = 0;
 
-GlobalActivityTracker::ModuleInfo::ModuleInfo() {}
+GlobalActivityTracker::ModuleInfo::ModuleInfo() = default;
 GlobalActivityTracker::ModuleInfo::ModuleInfo(ModuleInfo&& rhs) = default;
 GlobalActivityTracker::ModuleInfo::ModuleInfo(const ModuleInfo& rhs) = default;
-GlobalActivityTracker::ModuleInfo::~ModuleInfo() {}
+GlobalActivityTracker::ModuleInfo::~ModuleInfo() = default;
 
 GlobalActivityTracker::ModuleInfo& GlobalActivityTracker::ModuleInfo::operator=(
     ModuleInfo&& rhs) = default;
 GlobalActivityTracker::ModuleInfo& GlobalActivityTracker::ModuleInfo::operator=(
     const ModuleInfo& rhs) = default;
 
-GlobalActivityTracker::ModuleInfoRecord::ModuleInfoRecord() {}
-GlobalActivityTracker::ModuleInfoRecord::~ModuleInfoRecord() {}
+GlobalActivityTracker::ModuleInfoRecord::ModuleInfoRecord() = default;
+GlobalActivityTracker::ModuleInfoRecord::~ModuleInfoRecord() = default;
 
 bool GlobalActivityTracker::ModuleInfoRecord::DecodeTo(
     GlobalActivityTracker::ModuleInfo* info,
@@ -1225,7 +1225,7 @@ GlobalActivityTracker::ThreadSafeUserData::ThreadSafeUserData(void* memory,
                                                               int64_t pid)
     : ActivityUserData(memory, size, pid) {}
 
-GlobalActivityTracker::ThreadSafeUserData::~ThreadSafeUserData() {}
+GlobalActivityTracker::ThreadSafeUserData::~ThreadSafeUserData() = default;
 
 void GlobalActivityTracker::ThreadSafeUserData::Set(StringPiece name,
                                                     ValueType type,

base/debug/activity_tracker_unittest.cc

@@ -33,7 +33,7 @@ class TestActivityTracker : public ThreadActivityTracker {
       : ThreadActivityTracker(memset(memory.get(), 0, mem_size), mem_size),
         mem_segment_(std::move(memory)) {}
 
-  ~TestActivityTracker() override {}
+  ~TestActivityTracker() override = default;
 
  private:
   std::unique_ptr<char[]> mem_segment_;
@@ -49,7 +49,7 @@ class ActivityTrackerTest : public testing::Test {
 
   using ActivityId = ThreadActivityTracker::ActivityId;
 
-  ActivityTrackerTest() {}
+  ActivityTrackerTest() = default;
 
   ~ActivityTrackerTest() override {
     GlobalActivityTracker* global_tracker = GlobalActivityTracker::Get();
@@ -260,7 +260,7 @@ class SimpleLockThread : public SimpleThread {
         data_changed_(false),
         is_running_(false) {}
 
-  ~SimpleLockThread() override {}
+  ~SimpleLockThread() override = default;
 
   void Run() override {
     ThreadActivityTracker* tracker =
@@ -401,7 +401,7 @@ class SimpleActivityThread : public SimpleThread {
         exit_(false),
         exit_condition_(&lock_) {}
 
-  ~SimpleActivityThread() override {}
+  ~SimpleActivityThread() override = default;
 
   void Run() override {
     ThreadActivityTracker::ActivityId id =

base/debug/stack_trace_posix.cc

@@ -129,7 +129,7 @@ class BacktraceOutputHandler {
   virtual void HandleOutput(const char* output) = 0;
 
  protected:
-  virtual ~BacktraceOutputHandler() {}
+  virtual ~BacktraceOutputHandler() = default;
 };
 
 #if !defined(__UCLIBC__) && !defined(_AIX)
@@ -415,7 +415,7 @@ void StackDumpSignalHandler(int signal, siginfo_t* info, void* void_context) {
 
 class PrintBacktraceOutputHandler : public BacktraceOutputHandler {
  public:
-  PrintBacktraceOutputHandler() {}
+  PrintBacktraceOutputHandler() = default;
 
   void HandleOutput(const char* output) override {
     // NOTE: This code MUST be async-signal safe (it's used by in-process