Add missing, and remove unnecessary, 'explicit' from constructors. (base/)

The style guide says that constructors which can be called with one
argument should be explicit.

For constructors which cannot be called with exactly one argument,
there is no reason to mark them explicit.

BUG=163357


Review URL: https://chromiumcodereview.appspot.com/11779022

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@176881 0039d316-1c4b-4281-b951-d872f2087c98

27 files changed, 51 insertions, 47 deletions

diff --git a/base/bind_unittest.cc b/base/bind_unittest.cc
index 1d808a6..5ca67e9 100644
--- a/base/bind_unittest.cc
+++ b/base/bind_unittest.cc
@@ -106,7 +106,7 @@ class CopyCounter {
   }
 
   // Probing for copies from coercion.
-  CopyCounter(const DerivedCopyCounter& other)
+  explicit CopyCounter(const DerivedCopyCounter& other)
       : copies_(other.copies_),
         assigns_(other.assigns_) {
     (*copies_)++;
@@ -766,7 +766,7 @@ TEST_F(BindTest, ArgumentCopies) {
   DerivedCopyCounter dervied(&copies, &assigns);
   Callback<void(CopyCounter)> coerce_cb =
       Bind(&VoidPolymorphic1<CopyCounter>);
-  coerce_cb.Run(dervied);
+  coerce_cb.Run(CopyCounter(dervied));
   EXPECT_GE(2, copies);
   EXPECT_EQ(0, assigns);
 }
diff --git a/base/callback_unittest.cc b/base/callback_unittest.cc
index 2c2bef1a..6103b2e 100644
--- a/base/callback_unittest.cc
+++ b/base/callback_unittest.cc
@@ -148,7 +148,7 @@ TEST_F(CallbackTest, ResetAndReturn) {
 
 class CallbackOwner : public base::RefCounted<CallbackOwner> {
  public:
-  CallbackOwner(bool* deleted) {
+  explicit CallbackOwner(bool* deleted) {
     callback_ = Bind(&CallbackOwner::Unused, this);
     deleted_ = deleted;
   }
diff --git a/base/containers/small_map_unittest.cc b/base/containers/small_map_unittest.cc
index d1c8680..c90a303 100644
--- a/base/containers/small_map_unittest.cc
+++ b/base/containers/small_map_unittest.cc
@@ -424,7 +424,8 @@ namespace {
 class hash_map_add_item : public hash_map<int, int> {
  public:
   hash_map_add_item() : hash_map<int, int>() {}
-  hash_map_add_item(const std::pair<int, int>& item) : hash_map<int, int>() {
+  explicit hash_map_add_item(const std::pair<int, int>& item)
+      : hash_map<int, int>() {
     insert(item);
   }
 };
diff --git a/base/debug/stack_trace_posix.cc b/base/debug/stack_trace_posix.cc
index 7930a40..e1e006e 100644
--- a/base/debug/stack_trace_posix.cc
+++ b/base/debug/stack_trace_posix.cc
@@ -323,7 +323,7 @@ class PrintBacktraceOutputHandler : public BacktraceOutputHandler {
 
 class StreamBacktraceOutputHandler : public BacktraceOutputHandler {
  public:
-  StreamBacktraceOutputHandler(std::ostream* os) : os_(os) {
+  explicit StreamBacktraceOutputHandler(std::ostream* os) : os_(os) {
   }
 
   virtual void HandleOutput(const char* output) {
diff --git a/base/debug/trace_event.h b/base/debug/trace_event.h
index 58bd023..fc8897e 100644
--- a/base/debug/trace_event.h
+++ b/base/debug/trace_event.h
@@ -719,33 +719,33 @@ class TraceID {
      unsigned long long data_;
   };
 
-  explicit TraceID(const void* id, unsigned char* flags)
+  TraceID(const void* id, unsigned char* flags)
       : data_(static_cast<unsigned long long>(
               reinterpret_cast<unsigned long>(id))) {
     *flags |= TRACE_EVENT_FLAG_MANGLE_ID;
   }
-  explicit TraceID(ForceMangle id, unsigned char* flags) : data_(id.data()) {
+  TraceID(ForceMangle id, unsigned char* flags) : data_(id.data()) {
     *flags |= TRACE_EVENT_FLAG_MANGLE_ID;
   }
-  explicit TraceID(unsigned long long id, unsigned char* flags)
+  TraceID(unsigned long long id, unsigned char* flags)
       : data_(id) { (void)flags; }
-  explicit TraceID(unsigned long id, unsigned char* flags)
+  TraceID(unsigned long id, unsigned char* flags)
       : data_(id) { (void)flags; }
-  explicit TraceID(unsigned int id, unsigned char* flags)
+  TraceID(unsigned int id, unsigned char* flags)
       : data_(id) { (void)flags; }
-  explicit TraceID(unsigned short id, unsigned char* flags)
+  TraceID(unsigned short id, unsigned char* flags)
       : data_(id) { (void)flags; }
-  explicit TraceID(unsigned char id, unsigned char* flags)
+  TraceID(unsigned char id, unsigned char* flags)
       : data_(id) { (void)flags; }
-  explicit TraceID(long long id, unsigned char* flags)
+  TraceID(long long id, unsigned char* flags)
       : data_(static_cast<unsigned long long>(id)) { (void)flags; }
-  explicit TraceID(long id, unsigned char* flags)
+  TraceID(long id, unsigned char* flags)
       : data_(static_cast<unsigned long long>(id)) { (void)flags; }
-  explicit TraceID(int id, unsigned char* flags)
+  TraceID(int id, unsigned char* flags)
       : data_(static_cast<unsigned long long>(id)) { (void)flags; }
-  explicit TraceID(short id, unsigned char* flags)
+  TraceID(short id, unsigned char* flags)
       : data_(static_cast<unsigned long long>(id)) { (void)flags; }
-  explicit TraceID(signed char id, unsigned char* flags)
+  TraceID(signed char id, unsigned char* flags)
       : data_(static_cast<unsigned long long>(id)) { (void)flags; }
 
   unsigned long long data() const { return data_; }
diff --git a/base/event_recorder.h b/base/event_recorder.h
index 32e1124..979e806 100644
--- a/base/event_recorder.h
+++ b/base/event_recorder.h
@@ -74,7 +74,7 @@ class BASE_EXPORT EventRecorder {
   // Create a new EventRecorder.  Events are saved to the file filename.
   // If the file already exists, it will be deleted before recording
   // starts.
-  explicit EventRecorder()
+  EventRecorder()
       : is_recording_(false),
         is_playing_(false),
 #if defined(OS_WIN)
diff --git a/base/i18n/char_iterator.h b/base/i18n/char_iterator.h
index 431e350..25bcf9a 100644
--- a/base/i18n/char_iterator.h
+++ b/base/i18n/char_iterator.h
@@ -30,7 +30,7 @@ namespace i18n {
 class BASE_I18N_EXPORT UTF8CharIterator {
  public:
   // Requires |str| to live as long as the UTF8CharIterator does.
-  UTF8CharIterator(const std::string* str);
+  explicit UTF8CharIterator(const std::string* str);
   ~UTF8CharIterator();
 
   // Return the starting array index of the current character within the
@@ -76,7 +76,7 @@ class BASE_I18N_EXPORT UTF8CharIterator {
 class BASE_I18N_EXPORT UTF16CharIterator {
  public:
   // Requires |str| to live as long as the UTF16CharIterator does.
-  UTF16CharIterator(const string16* str);
+  explicit UTF16CharIterator(const string16* str);
   UTF16CharIterator(const char16* str, size_t str_len);
   ~UTF16CharIterator();
 
diff --git a/base/memory/ref_counted_memory.h b/base/memory/ref_counted_memory.h
index b99871b..fd5e8a0 100644
--- a/base/memory/ref_counted_memory.h
+++ b/base/memory/ref_counted_memory.h
@@ -65,7 +65,7 @@ class BASE_EXPORT RefCountedBytes : public RefCountedMemory {
   RefCountedBytes();
 
   // Constructs a RefCountedBytes object by _copying_ from |initializer|.
-  RefCountedBytes(const std::vector<unsigned char>& initializer);
+  explicit RefCountedBytes(const std::vector<unsigned char>& initializer);
 
   // Constructs a RefCountedBytes object by performing a swap. (To non
   // destructively build a RefCountedBytes, use the constructor that takes a
diff --git a/base/message_pump_libevent_unittest.cc b/base/message_pump_libevent_unittest.cc
index 3e06478..c7d908e 100644
--- a/base/message_pump_libevent_unittest.cc
+++ b/base/message_pump_libevent_unittest.cc
@@ -85,7 +85,7 @@ TEST_F(MessagePumpLibeventTest, TestWatchingFromBadThread) {
 
 class BaseWatcher : public MessagePumpLibevent::Watcher {
  public:
-  BaseWatcher(MessagePumpLibevent::FileDescriptorWatcher* controller)
+  explicit BaseWatcher(MessagePumpLibevent::FileDescriptorWatcher* controller)
       : controller_(controller) {
     DCHECK(controller_);
   }
diff --git a/base/metrics/bucket_ranges.h b/base/metrics/bucket_ranges.h
index 90b9047..210b9a7 100644
--- a/base/metrics/bucket_ranges.h
+++ b/base/metrics/bucket_ranges.h
@@ -30,7 +30,7 @@ class BASE_EXPORT BucketRanges {
  public:
   typedef std::vector<HistogramBase::Sample> Ranges;
 
-  BucketRanges(size_t num_ranges);
+  explicit BucketRanges(size_t num_ranges);
   ~BucketRanges();
 
   size_t size() const { return ranges_.size(); }
diff --git a/base/metrics/histogram_base.h b/base/metrics/histogram_base.h
index 69e1437..949e864 100644
--- a/base/metrics/histogram_base.h
+++ b/base/metrics/histogram_base.h
@@ -69,7 +69,7 @@ class BASE_EXPORT HistogramBase {
     kHexRangePrintingFlag = 0x8000,
   };
 
-  HistogramBase(const std::string& name);
+  explicit HistogramBase(const std::string& name);
   virtual ~HistogramBase();
 
   std::string histogram_name() const { return histogram_name_; }
diff --git a/base/metrics/histogram_samples.cc b/base/metrics/histogram_samples.cc
index e375952..0e0eeb4 100644
--- a/base/metrics/histogram_samples.cc
+++ b/base/metrics/histogram_samples.cc
@@ -13,7 +13,7 @@ namespace {
 
 class SampleCountPickleIterator : public SampleCountIterator {
  public:
-  SampleCountPickleIterator(PickleIterator* iter);
+  explicit SampleCountPickleIterator(PickleIterator* iter);
 
   virtual bool Done() const OVERRIDE;
   virtual void Next() OVERRIDE;
diff --git a/base/metrics/sample_map.h b/base/metrics/sample_map.h
index 22c391bb..cdd1138 100644
--- a/base/metrics/sample_map.h
+++ b/base/metrics/sample_map.h
@@ -46,7 +46,7 @@ class BASE_EXPORT_PRIVATE SampleMapIterator : public SampleCountIterator {
   typedef std::map<HistogramBase::Sample, HistogramBase::Count>
       SampleToCountMap;
 
-  SampleMapIterator(const SampleToCountMap& sample_counts);
+  explicit SampleMapIterator(const SampleToCountMap& sample_counts);
   virtual ~SampleMapIterator();
 
   // SampleCountIterator implementation:
diff --git a/base/metrics/sparse_histogram.h b/base/metrics/sparse_histogram.h
index 346ffeb..ae4530a 100644
--- a/base/metrics/sparse_histogram.h
+++ b/base/metrics/sparse_histogram.h
@@ -46,7 +46,7 @@ class BASE_EXPORT_PRIVATE SparseHistogram : public HistogramBase {
 
  private:
   // Clients should always use FactoryGet to create SparseHistogram.
-  SparseHistogram(const std::string& name);
+  explicit SparseHistogram(const std::string& name);
 
   friend BASE_EXPORT_PRIVATE HistogramBase* DeserializeHistogramInfo(
       PickleIterator* iter);
diff --git a/base/synchronization/condition_variable_unittest.cc b/base/synchronization/condition_variable_unittest.cc
index 4162d4f..a6426cf 100644
--- a/base/synchronization/condition_variable_unittest.cc
+++ b/base/synchronization/condition_variable_unittest.cc
@@ -35,7 +35,7 @@ class ConditionVariableTest : public PlatformTest {
   const TimeDelta kSixtyMs;
   const TimeDelta kOneHundredMs;
 
-  explicit ConditionVariableTest()
+  ConditionVariableTest()
       : kZeroMs(TimeDelta::FromMilliseconds(0)),
         kTenMs(TimeDelta::FromMilliseconds(10)),
         kThirtyMs(TimeDelta::FromMilliseconds(30)),
diff --git a/base/synchronization/lock_unittest.cc b/base/synchronization/lock_unittest.cc
index a048f85..e87571d 100644
--- a/base/synchronization/lock_unittest.cc
+++ b/base/synchronization/lock_unittest.cc
@@ -16,7 +16,7 @@ namespace base {
 
 class BasicLockTestThread : public PlatformThread::Delegate {
  public:
-  BasicLockTestThread(Lock* lock) : lock_(lock), acquired_(0) {}
+  explicit BasicLockTestThread(Lock* lock) : lock_(lock), acquired_(0) {}
 
   virtual void ThreadMain() OVERRIDE {
     for (int i = 0; i < 10; i++) {
@@ -91,7 +91,7 @@ TEST(LockTest, Basic) {
 
 class TryLockTestThread : public PlatformThread::Delegate {
  public:
-  TryLockTestThread(Lock* lock) : lock_(lock), got_lock_(false) {}
+  explicit TryLockTestThread(Lock* lock) : lock_(lock), got_lock_(false) {}
 
   virtual void ThreadMain() OVERRIDE {
     got_lock_ = lock_->Try();
diff --git a/base/task_runner.cc b/base/task_runner.cc
index b0563d4..5860f28 100644
--- a/base/task_runner.cc
+++ b/base/task_runner.cc
@@ -17,7 +17,7 @@ namespace {
 // possible to merge the two.
 class PostTaskAndReplyTaskRunner : public internal::PostTaskAndReplyImpl {
  public:
-  PostTaskAndReplyTaskRunner(TaskRunner* destination);
+  explicit PostTaskAndReplyTaskRunner(TaskRunner* destination);
 
  private:
   virtual bool PostTask(const tracked_objects::Location& from_here,
diff --git a/base/test/trace_event_analyzer.h b/base/test/trace_event_analyzer.h
index a472639..e2bb7de 100644
--- a/base/test/trace_event_analyzer.h
+++ b/base/test/trace_event_analyzer.h
@@ -352,7 +352,7 @@ class Query {
 
   // Find BEGIN events of given |name| which also have associated END events.
   static Query MatchBeginName(const std::string& name) {
-    return (Query(EVENT_NAME) == name) && MatchBeginWithEnd();
+    return (Query(EVENT_NAME) == Query(name)) && MatchBeginWithEnd();
   }
 
   // Match given Process ID and Thread ID.
@@ -452,16 +452,16 @@ class Query {
   };
 
   // Compare with the given member.
-  Query(TraceEventMember member);
+  explicit Query(TraceEventMember member);
 
   // Compare with the given member argument value.
   Query(TraceEventMember member, const std::string& arg_name);
 
   // Compare with the given string.
-  Query(const std::string& str);
+  explicit Query(const std::string& str);
 
   // Compare with the given number.
-  Query(double num);
+  explicit Query(double num);
 
   // Construct a boolean Query that returns (left <binary_op> right).
   Query(const Query& left, const Query& right, Operator binary_op);
diff --git a/base/thread_task_runner_handle.h b/base/thread_task_runner_handle.h
index 599d15b..348c071 100644
--- a/base/thread_task_runner_handle.h
+++ b/base/thread_task_runner_handle.h
@@ -22,7 +22,7 @@ class BASE_EXPORT ThreadTaskRunnerHandle {
   // Gets the SingleThreadTaskRunner for the current thread.
   static scoped_refptr<SingleThreadTaskRunner> Get();
 
-  ThreadTaskRunnerHandle(
+  explicit ThreadTaskRunnerHandle(
       const scoped_refptr<SingleThreadTaskRunner>& task_runner);
   ~ThreadTaskRunnerHandle();
 
diff --git a/base/threading/non_thread_safe_unittest.cc b/base/threading/non_thread_safe_unittest.cc
index ee31701..8a82a63 100644
--- a/base/threading/non_thread_safe_unittest.cc
+++ b/base/threading/non_thread_safe_unittest.cc
@@ -47,7 +47,7 @@ class NonThreadSafeClass : public NonThreadSafe {
 // Calls NonThreadSafeClass::DoStuff on another thread.
 class CallDoStuffOnThread : public SimpleThread {
  public:
-  CallDoStuffOnThread(NonThreadSafeClass* non_thread_safe_class)
+  explicit CallDoStuffOnThread(NonThreadSafeClass* non_thread_safe_class)
       : SimpleThread("call_do_stuff_on_thread"),
         non_thread_safe_class_(non_thread_safe_class) {
   }
@@ -65,7 +65,8 @@ class CallDoStuffOnThread : public SimpleThread {
 // Deletes NonThreadSafeClass on a different thread.
 class DeleteNonThreadSafeClassOnThread : public SimpleThread {
  public:
-  DeleteNonThreadSafeClassOnThread(NonThreadSafeClass* non_thread_safe_class)
+  explicit DeleteNonThreadSafeClassOnThread(
+      NonThreadSafeClass* non_thread_safe_class)
       : SimpleThread("delete_non_thread_safe_class_on_thread"),
         non_thread_safe_class_(non_thread_safe_class) {
   }
diff --git a/base/threading/thread_checker_unittest.cc b/base/threading/thread_checker_unittest.cc
index 026cfd9..ae96923 100644
--- a/base/threading/thread_checker_unittest.cc
+++ b/base/threading/thread_checker_unittest.cc
@@ -47,7 +47,7 @@ class ThreadCheckerClass : public ThreadChecker {
 // Calls ThreadCheckerClass::DoStuff on another thread.
 class CallDoStuffOnThread : public base::SimpleThread {
  public:
-  CallDoStuffOnThread(ThreadCheckerClass* thread_checker_class)
+  explicit CallDoStuffOnThread(ThreadCheckerClass* thread_checker_class)
       : SimpleThread("call_do_stuff_on_thread"),
         thread_checker_class_(thread_checker_class) {
   }
@@ -65,7 +65,8 @@ class CallDoStuffOnThread : public base::SimpleThread {
 // Deletes ThreadCheckerClass on a different thread.
 class DeleteThreadCheckerClassOnThread : public base::SimpleThread {
  public:
-  DeleteThreadCheckerClassOnThread(ThreadCheckerClass* thread_checker_class)
+  explicit DeleteThreadCheckerClassOnThread(
+      ThreadCheckerClass* thread_checker_class)
       : SimpleThread("delete_thread_checker_class_on_thread"),
         thread_checker_class_(thread_checker_class) {
   }
diff --git a/base/threading/thread_collision_warner.h b/base/threading/thread_collision_warner.h
index 2181cbd..d509a58 100644
--- a/base/threading/thread_collision_warner.h
+++ b/base/threading/thread_collision_warner.h
@@ -144,7 +144,7 @@ struct BASE_EXPORT DCheckAsserter : public AsserterBase {
 class BASE_EXPORT ThreadCollisionWarner {
  public:
   // The parameter asserter is there only for test purpose
-  ThreadCollisionWarner(AsserterBase* asserter = new DCheckAsserter())
+  explicit ThreadCollisionWarner(AsserterBase* asserter = new DCheckAsserter())
       : valid_thread_id_(0),
         counter_(0),
         asserter_(asserter) {}
diff --git a/base/threading/worker_pool.cc b/base/threading/worker_pool.cc
index 16cc061..9e45f8c 100644
--- a/base/threading/worker_pool.cc
+++ b/base/threading/worker_pool.cc
@@ -17,7 +17,8 @@ namespace {
 
 class PostTaskAndReplyWorkerPool : public internal::PostTaskAndReplyImpl {
  public:
-  PostTaskAndReplyWorkerPool(bool task_is_slow) : task_is_slow_(task_is_slow) {
+  explicit PostTaskAndReplyWorkerPool(bool task_is_slow)
+      : task_is_slow_(task_is_slow) {
   }
 
  private:
@@ -36,7 +37,7 @@ class PostTaskAndReplyWorkerPool : public internal::PostTaskAndReplyImpl {
 // Note that this class is RefCountedThreadSafe (inherited from TaskRunner).
 class WorkerPoolTaskRunner : public TaskRunner {
  public:
-  WorkerPoolTaskRunner(bool tasks_are_slow);
+  explicit WorkerPoolTaskRunner(bool tasks_are_slow);
 
   // TaskRunner implementation
   virtual bool PostDelayedTask(const tracked_objects::Location& from_here,
diff --git a/base/time.h b/base/time.h
index 78d7456..9c20b54 100644
--- a/base/time.h
+++ b/base/time.h
@@ -241,7 +241,7 @@ class BASE_EXPORT Time {
   };
 
   // Contains the NULL time. Use Time::Now() to get the current time.
-  explicit Time() : us_(0) {
+  Time() : us_(0) {
   }
 
   // Returns true if the time object has not been initialized.
diff --git a/base/timer.cc b/base/timer.cc
index 410d1b7..c7dcce0 100644
--- a/base/timer.cc
+++ b/base/timer.cc
@@ -18,7 +18,7 @@ namespace base {
 // - abandoned (orphaned) by Timer.
 class BaseTimerTaskInternal {
  public:
-  BaseTimerTaskInternal(Timer* timer)
+  explicit BaseTimerTaskInternal(Timer* timer)
       : timer_(timer) {
   }
 
diff --git a/base/timer_unittest.cc b/base/timer_unittest.cc
index 6fb89ad..1751a38 100644
--- a/base/timer_unittest.cc
+++ b/base/timer_unittest.cc
@@ -24,7 +24,7 @@ const int kNumTestingMessageLoops = arraysize(testing_message_loops);
 
 class OneShotTimerTester {
  public:
-  OneShotTimerTester(bool* did_run, unsigned milliseconds = 10)
+  explicit OneShotTimerTester(bool* did_run, unsigned milliseconds = 10)
       : did_run_(did_run),
         delay_ms_(milliseconds) {
   }
diff --git a/base/values.cc b/base/values.cc
index 7a21709..4c8968f 100644
--- a/base/values.cc
+++ b/base/values.cc
@@ -68,7 +68,7 @@ class ValueEquals {
   // Pass the value against which all consecutive calls of the () operator will
   // compare their argument to. This Value object must not be destroyed while
   // the ValueEquals is  in use.
-  ValueEquals(const Value* first) : first_(first) { }
+  explicit ValueEquals(const Value* first) : first_(first) { }
 
   bool operator ()(const Value* second) const {
     return first_->Equals(second);