Move message_loop to the message_loop directory.

Keep a forwarding header to avoid updating all callers.

BUG=
TBR=avi

Review URL: https://chromiumcodereview.appspot.com/15682017

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@206279 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 0 insertions, 834 deletions

diff --git a/base/message_loop.cc b/base/message_loop.cc
deleted file mode 100644
index 0d8a8ef..0000000
--- a/base/message_loop.cc
+++ /dev/null
@@ -1,834 +0,0 @@
-// 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/message_loop.h"
-
-#include <algorithm>
-
-#include "base/bind.h"
-#include "base/compiler_specific.h"
-#include "base/debug/alias.h"
-#include "base/debug/trace_event.h"
-#include "base/lazy_instance.h"
-#include "base/logging.h"
-#include "base/memory/scoped_ptr.h"
-#include "base/message_loop/message_loop_proxy_impl.h"
-#include "base/message_pump_default.h"
-#include "base/metrics/histogram.h"
-#include "base/metrics/statistics_recorder.h"
-#include "base/run_loop.h"
-#include "base/third_party/dynamic_annotations/dynamic_annotations.h"
-#include "base/thread_task_runner_handle.h"
-#include "base/threading/thread_local.h"
-#include "base/time.h"
-#include "base/tracked_objects.h"
-
-#if defined(OS_MACOSX)
-#include "base/message_pump_mac.h"
-#endif
-#if defined(OS_POSIX) && !defined(OS_IOS)
-#include "base/message_pump_libevent.h"
-#endif
-#if defined(OS_ANDROID)
-#include "base/message_pump_android.h"
-#endif
-
-#if defined(TOOLKIT_GTK)
-#include <gdk/gdk.h>
-#include <gdk/gdkx.h>
-#endif
-
-namespace base {
-
-namespace {
-
-// A lazily created thread local storage for quick access to a thread's message
-// loop, if one exists.  This should be safe and free of static constructors.
-LazyInstance<base::ThreadLocalPointer<MessageLoop> > lazy_tls_ptr =
-    LAZY_INSTANCE_INITIALIZER;
-
-// Logical events for Histogram profiling. Run with -message-loop-histogrammer
-// to get an accounting of messages and actions taken on each thread.
-const int kTaskRunEvent = 0x1;
-const int kTimerEvent = 0x2;
-
-// Provide range of message IDs for use in histogramming and debug display.
-const int kLeastNonZeroMessageId = 1;
-const int kMaxMessageId = 1099;
-const int kNumberOfDistinctMessagesDisplayed = 1100;
-
-// Provide a macro that takes an expression (such as a constant, or macro
-// constant) and creates a pair to initalize an array of pairs.  In this case,
-// our pair consists of the expressions value, and the "stringized" version
-// of the expression (i.e., the exrpression put in quotes).  For example, if
-// we have:
-//    #define FOO 2
-//    #define BAR 5
-// then the following:
-//    VALUE_TO_NUMBER_AND_NAME(FOO + BAR)
-// will expand to:
-//   {7, "FOO + BAR"}
-// We use the resulting array as an argument to our histogram, which reads the
-// number as a bucket identifier, and proceeds to use the corresponding name
-// in the pair (i.e., the quoted string) when printing out a histogram.
-#define VALUE_TO_NUMBER_AND_NAME(name) {name, #name},
-
-const LinearHistogram::DescriptionPair event_descriptions_[] = {
-  // Provide some pretty print capability in our histogram for our internal
-  // messages.
-
-  // A few events we handle (kindred to messages), and used to profile actions.
-  VALUE_TO_NUMBER_AND_NAME(kTaskRunEvent)
-  VALUE_TO_NUMBER_AND_NAME(kTimerEvent)
-
-  {-1, NULL}  // The list must be null terminated, per API to histogram.
-};
-
-bool enable_histogrammer_ = false;
-
-MessageLoop::MessagePumpFactory* message_pump_for_ui_factory_ = NULL;
-
-// Create a process-wide unique ID to represent this task in trace events. This
-// will be mangled with a Process ID hash to reduce the likelyhood of colliding
-// with MessageLoop pointers on other processes.
-uint64 GetTaskTraceID(const PendingTask& task, MessageLoop* loop) {
-  return (static_cast<uint64>(task.sequence_num) << 32) |
-         static_cast<uint64>(reinterpret_cast<intptr_t>(loop));
-}
-
-}  // namespace
-
-//------------------------------------------------------------------------------
-
-#if defined(OS_WIN)
-
-// Upon a SEH exception in this thread, it restores the original unhandled
-// exception filter.
-static int SEHFilter(LPTOP_LEVEL_EXCEPTION_FILTER old_filter) {
-  ::SetUnhandledExceptionFilter(old_filter);
-  return EXCEPTION_CONTINUE_SEARCH;
-}
-
-// Retrieves a pointer to the current unhandled exception filter. There
-// is no standalone getter method.
-static LPTOP_LEVEL_EXCEPTION_FILTER GetTopSEHFilter() {
-  LPTOP_LEVEL_EXCEPTION_FILTER top_filter = NULL;
-  top_filter = ::SetUnhandledExceptionFilter(0);
-  ::SetUnhandledExceptionFilter(top_filter);
-  return top_filter;
-}
-
-#endif  // defined(OS_WIN)
-
-//------------------------------------------------------------------------------
-
-MessageLoop::TaskObserver::TaskObserver() {
-}
-
-MessageLoop::TaskObserver::~TaskObserver() {
-}
-
-MessageLoop::DestructionObserver::~DestructionObserver() {
-}
-
-//------------------------------------------------------------------------------
-
-MessageLoop::MessageLoop(Type type)
-    : type_(type),
-      nestable_tasks_allowed_(true),
-      exception_restoration_(false),
-      message_histogram_(NULL),
-      run_loop_(NULL),
-#if defined(OS_WIN)
-      os_modal_loop_(false),
-#endif  // OS_WIN
-      next_sequence_num_(0) {
-  DCHECK(!current()) << "should only have one message loop per thread";
-  lazy_tls_ptr.Pointer()->Set(this);
-
-  message_loop_proxy_ = new MessageLoopProxyImpl();
-  thread_task_runner_handle_.reset(
-      new ThreadTaskRunnerHandle(message_loop_proxy_));
-
-// TODO(rvargas): Get rid of the OS guards.
-#if defined(OS_WIN)
-#define MESSAGE_PUMP_UI new MessagePumpForUI()
-#define MESSAGE_PUMP_IO new MessagePumpForIO()
-#elif defined(OS_IOS)
-#define MESSAGE_PUMP_UI MessagePumpMac::Create()
-#define MESSAGE_PUMP_IO new MessagePumpIOSForIO()
-#elif defined(OS_MACOSX)
-#define MESSAGE_PUMP_UI MessagePumpMac::Create()
-#define MESSAGE_PUMP_IO new MessagePumpLibevent()
-#elif defined(OS_NACL)
-// Currently NaCl doesn't have a UI MessageLoop.
-// TODO(abarth): Figure out if we need this.
-#define MESSAGE_PUMP_UI NULL
-// ipc_channel_nacl.cc uses a worker thread to do socket reads currently, and
-// doesn't require extra support for watching file descriptors.
-#define MESSAGE_PUMP_IO new MessagePumpDefault();
-#elif defined(OS_POSIX)  // POSIX but not MACOSX.
-#define MESSAGE_PUMP_UI new MessagePumpForUI()
-#define MESSAGE_PUMP_IO new MessagePumpLibevent()
-#else
-#error Not implemented
-#endif
-
-  if (type_ == TYPE_UI) {
-    if (message_pump_for_ui_factory_)
-      pump_ = message_pump_for_ui_factory_();
-    else
-      pump_ = MESSAGE_PUMP_UI;
-  } else if (type_ == TYPE_IO) {
-    pump_ = MESSAGE_PUMP_IO;
-  } else {
-    DCHECK_EQ(TYPE_DEFAULT, type_);
-    pump_ = new MessagePumpDefault();
-  }
-}
-
-MessageLoop::~MessageLoop() {
-  DCHECK_EQ(this, current());
-
-  DCHECK(!run_loop_);
-
-  // Clean up any unprocessed tasks, but take care: deleting a task could
-  // result in the addition of more tasks (e.g., via DeleteSoon).  We set a
-  // limit on the number of times we will allow a deleted task to generate more
-  // tasks.  Normally, we should only pass through this loop once or twice.  If
-  // we end up hitting the loop limit, then it is probably due to one task that
-  // is being stubborn.  Inspect the queues to see who is left.
-  bool did_work;
-  for (int i = 0; i < 100; ++i) {
-    DeletePendingTasks();
-    ReloadWorkQueue();
-    // If we end up with empty queues, then break out of the loop.
-    did_work = DeletePendingTasks();
-    if (!did_work)
-      break;
-  }
-  DCHECK(!did_work);
-
-  // Let interested parties have one last shot at accessing this.
-  FOR_EACH_OBSERVER(DestructionObserver, destruction_observers_,
-                    WillDestroyCurrentMessageLoop());
-
-  thread_task_runner_handle_.reset();
-
-  // Tell the message_loop_proxy that we are dying.
-  static_cast<MessageLoopProxyImpl*>(message_loop_proxy_.get())->
-      WillDestroyCurrentMessageLoop();
-  message_loop_proxy_ = NULL;
-
-  // OK, now make it so that no one can find us.
-  lazy_tls_ptr.Pointer()->Set(NULL);
-
-#if defined(OS_WIN)
-  // If we left the high-resolution timer activated, deactivate it now.
-  // Doing this is not-critical, it is mainly to make sure we track
-  // the high resolution timer activations properly in our unit tests.
-  if (!high_resolution_timer_expiration_.is_null()) {
-    Time::ActivateHighResolutionTimer(false);
-    high_resolution_timer_expiration_ = TimeTicks();
-  }
-#endif
-}
-
-// static
-MessageLoop* MessageLoop::current() {
-  // TODO(darin): sadly, we cannot enable this yet since people call us even
-  // when they have no intention of using us.
-  // DCHECK(loop) << "Ouch, did you forget to initialize me?";
-  return lazy_tls_ptr.Pointer()->Get();
-}
-
-// static
-void MessageLoop::EnableHistogrammer(bool enable) {
-  enable_histogrammer_ = enable;
-}
-
-// static
-bool MessageLoop::InitMessagePumpForUIFactory(MessagePumpFactory* factory) {
-  if (message_pump_for_ui_factory_)
-    return false;
-
-  message_pump_for_ui_factory_ = factory;
-  return true;
-}
-
-void MessageLoop::AddDestructionObserver(
-    DestructionObserver* destruction_observer) {
-  DCHECK_EQ(this, current());
-  destruction_observers_.AddObserver(destruction_observer);
-}
-
-void MessageLoop::RemoveDestructionObserver(
-    DestructionObserver* destruction_observer) {
-  DCHECK_EQ(this, current());
-  destruction_observers_.RemoveObserver(destruction_observer);
-}
-
-void MessageLoop::PostTask(
-    const tracked_objects::Location& from_here,
-    const Closure& task) {
-  DCHECK(!task.is_null()) << from_here.ToString();
-  PendingTask pending_task(
-      from_here, task, CalculateDelayedRuntime(TimeDelta()), true);
-  AddToIncomingQueue(&pending_task, false);
-}
-
-bool MessageLoop::TryPostTask(
-    const tracked_objects::Location& from_here,
-    const Closure& task) {
-  DCHECK(!task.is_null()) << from_here.ToString();
-  PendingTask pending_task(
-      from_here, task, CalculateDelayedRuntime(TimeDelta()), true);
-  return AddToIncomingQueue(&pending_task, true);
-}
-
-void MessageLoop::PostDelayedTask(
-    const tracked_objects::Location& from_here,
-    const Closure& task,
-    TimeDelta delay) {
-  DCHECK(!task.is_null()) << from_here.ToString();
-  PendingTask pending_task(
-      from_here, task, CalculateDelayedRuntime(delay), true);
-  AddToIncomingQueue(&pending_task, false);
-}
-
-void MessageLoop::PostNonNestableTask(
-    const tracked_objects::Location& from_here,
-    const Closure& task) {
-  DCHECK(!task.is_null()) << from_here.ToString();
-  PendingTask pending_task(
-      from_here, task, CalculateDelayedRuntime(TimeDelta()), false);
-  AddToIncomingQueue(&pending_task, false);
-}
-
-void MessageLoop::PostNonNestableDelayedTask(
-    const tracked_objects::Location& from_here,
-    const Closure& task,
-    TimeDelta delay) {
-  DCHECK(!task.is_null()) << from_here.ToString();
-  PendingTask pending_task(
-      from_here, task, CalculateDelayedRuntime(delay), false);
-  AddToIncomingQueue(&pending_task, false);
-}
-
-void MessageLoop::Run() {
-  RunLoop run_loop;
-  run_loop.Run();
-}
-
-void MessageLoop::RunUntilIdle() {
-  RunLoop run_loop;
-  run_loop.RunUntilIdle();
-}
-
-void MessageLoop::QuitWhenIdle() {
-  DCHECK_EQ(this, current());
-  if (run_loop_) {
-    run_loop_->quit_when_idle_received_ = true;
-  } else {
-    NOTREACHED() << "Must be inside Run to call Quit";
-  }
-}
-
-void MessageLoop::QuitNow() {
-  DCHECK_EQ(this, current());
-  if (run_loop_) {
-    pump_->Quit();
-  } else {
-    NOTREACHED() << "Must be inside Run to call Quit";
-  }
-}
-
-bool MessageLoop::IsType(Type type) const {
-  return type_ == type;
-}
-
-static void QuitCurrentWhenIdle() {
-  MessageLoop::current()->QuitWhenIdle();
-}
-
-// static
-Closure MessageLoop::QuitWhenIdleClosure() {
-  return Bind(&QuitCurrentWhenIdle);
-}
-
-void MessageLoop::SetNestableTasksAllowed(bool allowed) {
-  if (nestable_tasks_allowed_ != allowed) {
-    nestable_tasks_allowed_ = allowed;
-    if (!nestable_tasks_allowed_)
-      return;
-    // Start the native pump if we are not already pumping.
-    pump_->ScheduleWork();
-  }
-}
-
-bool MessageLoop::NestableTasksAllowed() const {
-  return nestable_tasks_allowed_;
-}
-
-bool MessageLoop::IsNested() {
-  return run_loop_->run_depth_ > 1;
-}
-
-void MessageLoop::AddTaskObserver(TaskObserver* task_observer) {
-  DCHECK_EQ(this, current());
-  task_observers_.AddObserver(task_observer);
-}
-
-void MessageLoop::RemoveTaskObserver(TaskObserver* task_observer) {
-  DCHECK_EQ(this, current());
-  task_observers_.RemoveObserver(task_observer);
-}
-
-void MessageLoop::AssertIdle() const {
-  // We only check |incoming_queue_|, since we don't want to lock |work_queue_|.
-  AutoLock lock(incoming_queue_lock_);
-  DCHECK(incoming_queue_.empty());
-}
-
-bool MessageLoop::is_running() const {
-  DCHECK_EQ(this, current());
-  return run_loop_ != NULL;
-}
-
-//------------------------------------------------------------------------------
-
-// Runs the loop in two different SEH modes:
-// enable_SEH_restoration_ = false : any unhandled exception goes to the last
-// one that calls SetUnhandledExceptionFilter().
-// enable_SEH_restoration_ = true : any unhandled exception goes to the filter
-// that was existed before the loop was run.
-void MessageLoop::RunHandler() {
-#if defined(OS_WIN)
-  if (exception_restoration_) {
-    RunInternalInSEHFrame();
-    return;
-  }
-#endif
-
-  RunInternal();
-}
-
-#if defined(OS_WIN)
-__declspec(noinline) void MessageLoop::RunInternalInSEHFrame() {
-  LPTOP_LEVEL_EXCEPTION_FILTER current_filter = GetTopSEHFilter();
-  __try {
-    RunInternal();
-  } __except(SEHFilter(current_filter)) {
-  }
-  return;
-}
-#endif
-
-void MessageLoop::RunInternal() {
-  DCHECK_EQ(this, current());
-
-  StartHistogrammer();
-
-#if !defined(OS_MACOSX) && !defined(OS_ANDROID)
-  if (run_loop_->dispatcher_ && type() == TYPE_UI) {
-    static_cast<MessagePumpForUI*>(pump_.get())->
-        RunWithDispatcher(this, run_loop_->dispatcher_);
-    return;
-  }
-#endif
-
-  pump_->Run(this);
-}
-
-bool MessageLoop::ProcessNextDelayedNonNestableTask() {
-  if (run_loop_->run_depth_ != 1)
-    return false;
-
-  if (deferred_non_nestable_work_queue_.empty())
-    return false;
-
-  PendingTask pending_task = deferred_non_nestable_work_queue_.front();
-  deferred_non_nestable_work_queue_.pop();
-
-  RunTask(pending_task);
-  return true;
-}
-
-void MessageLoop::RunTask(const PendingTask& pending_task) {
-  TRACE_EVENT_FLOW_END0("task", "MessageLoop::PostTask",
-      TRACE_ID_MANGLE(GetTaskTraceID(pending_task, this)));
-  TRACE_EVENT2("task", "MessageLoop::RunTask",
-               "src_file", pending_task.posted_from.file_name(),
-               "src_func", pending_task.posted_from.function_name());
-  DCHECK(nestable_tasks_allowed_);
-  // Execute the task and assume the worst: It is probably not reentrant.
-  nestable_tasks_allowed_ = false;
-
-  // Before running the task, store the program counter where it was posted
-  // and deliberately alias it to ensure it is on the stack if the task
-  // crashes. Be careful not to assume that the variable itself will have the
-  // expected value when displayed by the optimizer in an optimized build.
-  // Look at a memory dump of the stack.
-  const void* program_counter =
-      pending_task.posted_from.program_counter();
-  debug::Alias(&program_counter);
-
-  HistogramEvent(kTaskRunEvent);
-
-  tracked_objects::TrackedTime start_time =
-      tracked_objects::ThreadData::NowForStartOfRun(pending_task.birth_tally);
-
-  FOR_EACH_OBSERVER(TaskObserver, task_observers_,
-                    WillProcessTask(pending_task));
-  pending_task.task.Run();
-  FOR_EACH_OBSERVER(TaskObserver, task_observers_,
-                    DidProcessTask(pending_task));
-
-  tracked_objects::ThreadData::TallyRunOnNamedThreadIfTracking(pending_task,
-      start_time, tracked_objects::ThreadData::NowForEndOfRun());
-
-  nestable_tasks_allowed_ = true;
-}
-
-bool MessageLoop::DeferOrRunPendingTask(const PendingTask& pending_task) {
-  if (pending_task.nestable || run_loop_->run_depth_ == 1) {
-    RunTask(pending_task);
-    // Show that we ran a task (Note: a new one might arrive as a
-    // consequence!).
-    return true;
-  }
-
-  // We couldn't run the task now because we're in a nested message loop
-  // and the task isn't nestable.
-  deferred_non_nestable_work_queue_.push(pending_task);
-  return false;
-}
-
-void MessageLoop::AddToDelayedWorkQueue(const PendingTask& pending_task) {
-  // Move to the delayed work queue.
-  delayed_work_queue_.push(pending_task);
-}
-
-void MessageLoop::ReloadWorkQueue() {
-  // We can improve performance of our loading tasks from incoming_queue_ to
-  // work_queue_ by waiting until the last minute (work_queue_ is empty) to
-  // load.  That reduces the number of locks-per-task significantly when our
-  // queues get large.
-  if (!work_queue_.empty())
-    return;  // Wait till we *really* need to lock and load.
-
-  // Acquire all we can from the inter-thread queue with one lock acquisition.
-  {
-    AutoLock lock(incoming_queue_lock_);
-    if (incoming_queue_.empty())
-      return;
-    incoming_queue_.Swap(&work_queue_);  // Constant time
-    DCHECK(incoming_queue_.empty());
-  }
-}
-
-bool MessageLoop::DeletePendingTasks() {
-  bool did_work = !work_queue_.empty();
-  while (!work_queue_.empty()) {
-    PendingTask pending_task = work_queue_.front();
-    work_queue_.pop();
-    if (!pending_task.delayed_run_time.is_null()) {
-      // We want to delete delayed tasks in the same order in which they would
-      // normally be deleted in case of any funny dependencies between delayed
-      // tasks.
-      AddToDelayedWorkQueue(pending_task);
-    }
-  }
-  did_work |= !deferred_non_nestable_work_queue_.empty();
-  while (!deferred_non_nestable_work_queue_.empty()) {
-    deferred_non_nestable_work_queue_.pop();
-  }
-  did_work |= !delayed_work_queue_.empty();
-
-  // Historically, we always delete the task regardless of valgrind status. It's
-  // not completely clear why we want to leak them in the loops above.  This
-  // code is replicating legacy behavior, and should not be considered
-  // absolutely "correct" behavior.  See TODO above about deleting all tasks
-  // when it's safe.
-  while (!delayed_work_queue_.empty()) {
-    delayed_work_queue_.pop();
-  }
-  return did_work;
-}
-
-TimeTicks MessageLoop::CalculateDelayedRuntime(TimeDelta delay) {
-  TimeTicks delayed_run_time;
-  if (delay > TimeDelta()) {
-    delayed_run_time = TimeTicks::Now() + delay;
-
-#if defined(OS_WIN)
-    if (high_resolution_timer_expiration_.is_null()) {
-      // Windows timers are granular to 15.6ms.  If we only set high-res
-      // timers for those under 15.6ms, then a 18ms timer ticks at ~32ms,
-      // which as a percentage is pretty inaccurate.  So enable high
-      // res timers for any timer which is within 2x of the granularity.
-      // This is a tradeoff between accuracy and power management.
-      bool needs_high_res_timers = delay.InMilliseconds() <
-          (2 * Time::kMinLowResolutionThresholdMs);
-      if (needs_high_res_timers) {
-        if (Time::ActivateHighResolutionTimer(true)) {
-          high_resolution_timer_expiration_ = TimeTicks::Now() +
-              TimeDelta::FromMilliseconds(kHighResolutionTimerModeLeaseTimeMs);
-        }
-      }
-    }
-#endif
-  } else {
-    DCHECK_EQ(delay.InMilliseconds(), 0) << "delay should not be negative";
-  }
-
-#if defined(OS_WIN)
-  if (!high_resolution_timer_expiration_.is_null()) {
-    if (TimeTicks::Now() > high_resolution_timer_expiration_) {
-      Time::ActivateHighResolutionTimer(false);
-      high_resolution_timer_expiration_ = TimeTicks();
-    }
-  }
-#endif
-
-  return delayed_run_time;
-}
-
-// Possibly called on a background thread!
-bool MessageLoop::AddToIncomingQueue(PendingTask* pending_task,
-                                     bool use_try_lock) {
-  // Warning: Don't try to short-circuit, and handle this thread's tasks more
-  // directly, as it could starve handling of foreign threads.  Put every task
-  // into this queue.
-
-  scoped_refptr<MessagePump> pump;
-  {
-    if (use_try_lock) {
-      if (!incoming_queue_lock_.Try()) {
-        pending_task->task.Reset();
-        return false;
-      }
-    } else {
-      incoming_queue_lock_.Acquire();
-    }
-    AutoLock locked(incoming_queue_lock_, AutoLock::AlreadyAcquired());
-    // Initialize the sequence number. The sequence number is used for delayed
-    // tasks (to faciliate FIFO sorting when two tasks have the same
-    // delayed_run_time value) and for identifying the task in about:tracing.
-    pending_task->sequence_num = next_sequence_num_++;
-
-    TRACE_EVENT_FLOW_BEGIN0("task", "MessageLoop::PostTask",
-        TRACE_ID_MANGLE(GetTaskTraceID(*pending_task, this)));
-
-    bool was_empty = incoming_queue_.empty();
-    incoming_queue_.push(*pending_task);
-    pending_task->task.Reset();
-    if (!was_empty)
-      return true;  // Someone else should have started the sub-pump.
-
-    pump = pump_;
-  }
-  // Since the incoming_queue_ may contain a task that destroys this message
-  // loop, we cannot exit incoming_queue_lock_ until we are done with |this|.
-  // We use a stack-based reference to the message pump so that we can call
-  // ScheduleWork outside of incoming_queue_lock_.
-
-  pump->ScheduleWork();
-  return true;
-}
-
-//------------------------------------------------------------------------------
-// Method and data for histogramming events and actions taken by each instance
-// on each thread.
-
-void MessageLoop::StartHistogrammer() {
-#if !defined(OS_NACL)  // NaCl build has no metrics code.
-  if (enable_histogrammer_ && !message_histogram_
-      && StatisticsRecorder::IsActive()) {
-    DCHECK(!thread_name_.empty());
-    message_histogram_ = LinearHistogram::FactoryGetWithRangeDescription(
-        "MsgLoop:" + thread_name_,
-        kLeastNonZeroMessageId, kMaxMessageId,
-        kNumberOfDistinctMessagesDisplayed,
-        message_histogram_->kHexRangePrintingFlag,
-        event_descriptions_);
-  }
-#endif
-}
-
-void MessageLoop::HistogramEvent(int event) {
-#if !defined(OS_NACL)
-  if (message_histogram_)
-    message_histogram_->Add(event);
-#endif
-}
-
-bool MessageLoop::DoWork() {
-  if (!nestable_tasks_allowed_) {
-    // Task can't be executed right now.
-    return false;
-  }
-
-  for (;;) {
-    ReloadWorkQueue();
-    if (work_queue_.empty())
-      break;
-
-    // Execute oldest task.
-    do {
-      PendingTask pending_task = work_queue_.front();
-      work_queue_.pop();
-      if (!pending_task.delayed_run_time.is_null()) {
-        AddToDelayedWorkQueue(pending_task);
-        // If we changed the topmost task, then it is time to reschedule.
-        if (delayed_work_queue_.top().task.Equals(pending_task.task))
-          pump_->ScheduleDelayedWork(pending_task.delayed_run_time);
-      } else {
-        if (DeferOrRunPendingTask(pending_task))
-          return true;
-      }
-    } while (!work_queue_.empty());
-  }
-
-  // Nothing happened.
-  return false;
-}
-
-bool MessageLoop::DoDelayedWork(TimeTicks* next_delayed_work_time) {
-  if (!nestable_tasks_allowed_ || delayed_work_queue_.empty()) {
-    recent_time_ = *next_delayed_work_time = TimeTicks();
-    return false;
-  }
-
-  // When we "fall behind," there will be a lot of tasks in the delayed work
-  // queue that are ready to run.  To increase efficiency when we fall behind,
-  // we will only call Time::Now() intermittently, and then process all tasks
-  // that are ready to run before calling it again.  As a result, the more we
-  // fall behind (and have a lot of ready-to-run delayed tasks), the more
-  // efficient we'll be at handling the tasks.
-
-  TimeTicks next_run_time = delayed_work_queue_.top().delayed_run_time;
-  if (next_run_time > recent_time_) {
-    recent_time_ = TimeTicks::Now();  // Get a better view of Now();
-    if (next_run_time > recent_time_) {
-      *next_delayed_work_time = next_run_time;
-      return false;
-    }
-  }
-
-  PendingTask pending_task = delayed_work_queue_.top();
-  delayed_work_queue_.pop();
-
-  if (!delayed_work_queue_.empty())
-    *next_delayed_work_time = delayed_work_queue_.top().delayed_run_time;
-
-  return DeferOrRunPendingTask(pending_task);
-}
-
-bool MessageLoop::DoIdleWork() {
-  if (ProcessNextDelayedNonNestableTask())
-    return true;
-
-  if (run_loop_->quit_when_idle_received_)
-    pump_->Quit();
-
-  return false;
-}
-
-void MessageLoop::DeleteSoonInternal(const tracked_objects::Location& from_here,
-                                     void(*deleter)(const void*),
-                                     const void* object) {
-  PostNonNestableTask(from_here, Bind(deleter, object));
-}
-
-void MessageLoop::ReleaseSoonInternal(
-    const tracked_objects::Location& from_here,
-    void(*releaser)(const void*),
-    const void* object) {
-  PostNonNestableTask(from_here, Bind(releaser, object));
-}
-
-//------------------------------------------------------------------------------
-// MessageLoopForUI
-
-#if defined(OS_WIN)
-void MessageLoopForUI::DidProcessMessage(const MSG& message) {
-  pump_win()->DidProcessMessage(message);
-}
-#endif  // defined(OS_WIN)
-
-#if defined(OS_ANDROID)
-void MessageLoopForUI::Start() {
-  // No Histogram support for UI message loop as it is managed by Java side
-  static_cast<MessagePumpForUI*>(pump_.get())->Start(this);
-}
-#endif
-
-#if defined(OS_IOS)
-void MessageLoopForUI::Attach() {
-  static_cast<MessagePumpUIApplication*>(pump_.get())->Attach(this);
-}
-#endif
-
-#if !defined(OS_MACOSX) && !defined(OS_NACL) && !defined(OS_ANDROID)
-void MessageLoopForUI::AddObserver(Observer* observer) {
-  pump_ui()->AddObserver(observer);
-}
-
-void MessageLoopForUI::RemoveObserver(Observer* observer) {
-  pump_ui()->RemoveObserver(observer);
-}
-
-#endif  //  !defined(OS_MACOSX) && !defined(OS_NACL) && !defined(OS_ANDROID)
-
-//------------------------------------------------------------------------------
-// MessageLoopForIO
-
-#if defined(OS_WIN)
-
-void MessageLoopForIO::RegisterIOHandler(HANDLE file, IOHandler* handler) {
-  pump_io()->RegisterIOHandler(file, handler);
-}
-
-bool MessageLoopForIO::RegisterJobObject(HANDLE job, IOHandler* handler) {
-  return pump_io()->RegisterJobObject(job, handler);
-}
-
-bool MessageLoopForIO::WaitForIOCompletion(DWORD timeout, IOHandler* filter) {
-  return pump_io()->WaitForIOCompletion(timeout, filter);
-}
-
-#elif defined(OS_IOS)
-
-bool MessageLoopForIO::WatchFileDescriptor(int fd,
-                                           bool persistent,
-                                           Mode mode,
-                                           FileDescriptorWatcher *controller,
-                                           Watcher *delegate) {
-  return pump_io()->WatchFileDescriptor(
-      fd,
-      persistent,
-      mode,
-      controller,
-      delegate);
-}
-
-#elif defined(OS_POSIX) && !defined(OS_NACL)
-
-bool MessageLoopForIO::WatchFileDescriptor(int fd,
-                                           bool persistent,
-                                           Mode mode,
-                                           FileDescriptorWatcher *controller,
-                                           Watcher *delegate) {
-  return pump_libevent()->WatchFileDescriptor(
-      fd,
-      persistent,
-      mode,
-      controller,
-      delegate);
-}
-
-#endif
-
-}  // namespace base