git-svn-id: svn://svn.chromium.org/chrome/trunk/src@739 0039d316-1c4b-4281-b951-d872f2087c98

7 files changed, 197 insertions, 160 deletions

diff --git a/base/message_loop.cc b/base/message_loop.cc
index 18f4448..5331bc6 100644
--- a/base/message_loop.cc
+++ b/base/message_loop.cc
@@ -108,17 +108,14 @@ static LPTOP_LEVEL_EXCEPTION_FILTER GetTopSEHFilter() {
 
 //------------------------------------------------------------------------------
 
-MessageLoop::MessageLoop()
-#pragma warning(suppress: 4355)  // OK, to use |this| in the initializer list.
-    : timer_manager_(this),
-      message_hwnd_(NULL),
-      exception_restoration_(false),
-      nestable_tasks_allowed_(true),
-      dispatcher_(NULL),
-      quit_received_(false),
-      quit_now_(false),
-      task_pump_message_pending_(false),
-      run_depth_(0) {
+MessageLoop::MessageLoop() : message_hwnd_(NULL),
+                             exception_restoration_(false),
+                             nestable_tasks_allowed_(true),
+                             dispatcher_(NULL),
+                             quit_received_(false),
+                             quit_now_(false),
+                             task_pump_message_pending_(false),
+                             run_depth_(0) {
   DCHECK(tls_index_) << "static initializer failed";
   DCHECK(!current()) << "should only have one message loop per thread";
   ThreadLocalStorage::Set(tls_index_, this);
@@ -409,11 +406,6 @@ LRESULT MessageLoop::WndProc(
         return 0;
       }
 
-      case WM_TIMER:
-        ProcessSomeTimers();         // Give the TimerManager a tickle.
-        DidChangeNextTimerExpiry();  // Maybe generate another WM_TIMER.
-        return 0;
-
       case kMsgQuit: {
         // TODO(jar): bug 1300541 The following assert should be used, but
         // currently too much code actually triggers the assert, especially in
@@ -662,22 +654,21 @@ bool MessageLoop::SignalWatcher(size_t object_index) {
 
 bool MessageLoop::RunTimerTask(Timer* timer) {
   HistogramEvent(kTimerEvent);
-
   Task* task = timer->task();
   if (task->is_owned_by_message_loop()) {
-    // We constructed it through PostDelayedTask().
+    // We constructed it through PostTask().
     DCHECK(!timer->repeating());
     timer->set_task(NULL);
     delete timer;
     task->ResetBirthTime();
     return QueueOrRunTask(task);
+  } else {
+    // This is an unknown timer task, and we *can't* delay running it, as a
+    // user might try to cancel it with TimerManager at any moment.
+    DCHECK(nestable_tasks_allowed_);
+    RunTask(task);
+    return true;
   }
-
-  // This is an unknown timer task, and we *can't* delay running it, as a user
-  // might try to cancel it with TimerManager at any moment.
-  DCHECK(nestable_tasks_allowed_);
-  RunTask(task);
-  return true;
 }
 
 void MessageLoop::DiscardTimer(Timer* timer) {
@@ -832,45 +823,6 @@ void MessageLoop::DeletePendingTasks() {
   */
 }
 
-void MessageLoop::DidChangeNextTimerExpiry() {
-#if defined(OS_WIN)
-  //
-  // We would *like* to provide high resolution timers.  Windows timers using
-  // SetTimer() have a 10ms granularity.  We have to use WM_TIMER as a wakeup
-  // mechanism because the application can enter modal windows loops where it
-  // is not running our MessageLoop; the only way to have our timers fire in
-  // these cases is to post messages there.
-  //
-  // To provide sub-10ms timers, we process timers directly from our run loop.
-  // For the common case, timers will be processed there as the run loop does
-  // its normal work.  However, we *also* set the system timer so that WM_TIMER
-  // events fire.  This mops up the case of timers not being able to work in
-  // modal message loops.  It is possible for the SetTimer to pop and have no
-  // pending timers, because they could have already been processed by the
-  // run loop itself.
-  //
-  // We use a single SetTimer corresponding to the timer that will expire
-  // soonest.  As new timers are created and destroyed, we update SetTimer.
-  // Getting a spurrious SetTimer event firing is benign, as we'll just be
-  // processing an empty timer queue.
-  //
-  int delay = timer_manager_.GetCurrentDelay(); 
-  if (delay == -1) {
-    KillTimer(message_hwnd_, reinterpret_cast<UINT_PTR>(this));
-  } else {
-    if (delay < USER_TIMER_MINIMUM)
-      delay = USER_TIMER_MINIMUM;
-    // Simulates malfunctioning, early firing timers. Pending tasks should only
-    // be invoked when the delay they specify has elapsed.
-    if (timer_manager_.use_broken_delay())
-      delay = 10;
-    // Create a WM_TIMER event that will wake us up to check for any pending
-    // timers (in case we are running within a nested, external sub-pump).
-    SetTimer(message_hwnd_, reinterpret_cast<UINT_PTR>(this), delay, NULL);
-  }
-#endif  // defined(OS_WIN)
-}
-
 //------------------------------------------------------------------------------
 // Implementation of the work_queue_ as a ProiritizedTaskQueue
 
diff --git a/base/message_loop.h b/base/message_loop.h
index 81c1e52..85535b4 100644
--- a/base/message_loop.h
+++ b/base/message_loop.h
@@ -365,8 +365,6 @@ class MessageLoop {
 
   //----------------------------------------------------------------------------
  private:
-  friend class TimerManager;  // So it can call DidChangeNextTimerExpiry
-
   struct ScopedStateSave {
     explicit ScopedStateSave(MessageLoop* loop)
         : loop_(loop),
@@ -575,9 +573,6 @@ class MessageLoop {
   // Post a task to our incomming queue.
   void PostTaskInternal(Task* task);
 
-  // Called by the TimerManager when its next timer changes.
-  void DidChangeNextTimerExpiry();
-
   // Start recording histogram info about events and action IF it was enabled
   // and IF the statistics recorder can accept a registration of our histogram.
   void StartHistogrammer();
diff --git a/base/timer.cc b/base/timer.cc
index c5e4e87..7c3a636 100644
--- a/base/timer.cc
+++ b/base/timer.cc
@@ -28,17 +28,52 @@
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 #include "base/timer.h"
-
-#include <math.h>
-#if defined(OS_WIN)
 #include <mmsystem.h>
-#endif
 
 #include "base/atomic_sequence_num.h"
 #include "base/logging.h"
 #include "base/message_loop.h"
 #include "base/task.h"
 
+// Note about hi-resolution timers.
+// This class would *like* to provide high resolution timers.  Windows timers
+// using SetTimer() have a 10ms granularity.  We have to use WM_TIMER as a
+// wakeup mechanism because the application can enter modal windows loops where
+// it is not running our MessageLoop; the only way to have our timers fire in
+// these cases is to post messages there.
+//
+// To provide sub-10ms timers, we process timers directly from our main
+// MessageLoop.  For the common case, timers will be processed there as the
+// message loop does its normal work.  However, we *also* set the system timer
+// so that WM_TIMER events fire.  This mops up the case of timers not being
+// able to work in modal message loops.  It is possible for the SetTimer to
+// pop and have no pending timers, because they could have already been
+// processed by the message loop itself.
+//
+// We use a single SetTimer corresponding to the timer that will expire
+// soonest.  As new timers are created and destroyed, we update SetTimer.
+// Getting a spurrious SetTimer event firing is benign, as we'll just be
+// processing an empty timer queue.
+
+static const wchar_t kWndClass[] = L"Chrome_TimerMessageWindow";
+
+static LRESULT CALLBACK MessageWndProc(HWND hwnd,
+                                       UINT message,
+                                       WPARAM wparam,
+                                       LPARAM lparam) {
+  if (message == WM_TIMER) {
+    // Timer not firing? Maybe you're suffering from a WM_PAINTstorm. Make sure
+    // any WM_PAINT handler you have calls BeginPaint and EndPaint to validate
+    // the invalid region, otherwise you will be flooded with paint messages
+    // that trump WM_TIMER when PeekMessage is called.
+    UINT_PTR timer_id = static_cast<UINT_PTR>(wparam);
+    TimerManager* tm = reinterpret_cast<TimerManager*>(timer_id);
+    return tm->MessageWndProc(hwnd, message, wparam, lparam);
+  }
+
+  return DefWindowProc(hwnd, message, wparam, lparam);
+}
+
 // A sequence number for all allocated times (used to break ties when
 // comparing times in the TimerManager, and assure FIFO execution sequence).
 static base::AtomicSequenceNumber timer_id_counter_;
@@ -55,14 +90,6 @@ Timer::Timer(int delay, Task* task, bool repeating)
   Reset();
 }
 
-int Timer::GetCurrentDelay() const {
-  // Be careful here.  Timers have a precision of microseconds, but this API is
-  // in milliseconds.  If there are 5.5ms left, should the delay be 5 or 6?  It
-  // should be 6 to avoid timers firing early.
-  double delay = ceil((fire_time_ - Time::Now()).InMillisecondsF());
-  return static_cast<int>(delay);
-}
-
 void Timer::Reset() {
   creation_time_ = Time::Now();
   fire_time_ = creation_time_ + TimeDelta::FromMilliseconds(delay_);
@@ -88,10 +115,11 @@ bool TimerPQueue::ContainsTimer(const Timer* timer) const {
 //-----------------------------------------------------------------------------
 // TimerManager
 
-TimerManager::TimerManager(MessageLoop* message_loop)
-    : use_broken_delay_(false),
-      message_loop_(message_loop) {
-#if defined(OS_WIN)
+TimerManager::TimerManager()
+    : message_hwnd_(NULL),
+      use_broken_delay_(false),
+      use_native_timers_(true),
+      message_loop_(NULL) {
   // We've experimented with all sorts of timers, and initially tried
   // to avoid using timeBeginPeriod because it does affect the system
   // globally.  However, after much investigation, it turns out that all
@@ -101,14 +129,18 @@ TimerManager::TimerManager(MessageLoop* message_loop)
   // needs to support a fast clock.  We may as well use this ourselves,
   // as it really is the best timer mechanism for our needs.
   timeBeginPeriod(1);
-#endif
+
+  // Initialize the Message HWND in the constructor so that the window
+  // belongs to the same thread as the message loop (this is important!)
+  GetMessageHWND();
 }
 
 TimerManager::~TimerManager() {
-#if defined(OS_WIN)
   // Match timeBeginPeriod() from construction.
   timeEndPeriod(1);
-#endif
+
+  if (message_hwnd_ != NULL)
+    DestroyWindow(message_hwnd_);
 
   // Be nice to unit tests, and discard and delete all timers along with the
   // embedded task objects by handing off to MessageLoop (which would have Run()
@@ -136,7 +168,7 @@ void TimerManager::StopTimer(Timer* timer) {
     timers_.RemoveTimer(timer);
   } else {
     timers_.pop();
-    DidChangeNextTimer();
+    UpdateWindowsWmTimer();  // We took away the head of our queue.
   }
 }
 
@@ -158,6 +190,7 @@ Timer* TimerManager::PeekTopTimer() {
 
 bool TimerManager::RunSomePendingTimers() {
   bool did_work = false;
+  bool allowed_to_run = message_loop()->NestableTasksAllowed();
   // Process a small group of timers.  Cap the maximum number of timers we can
   // process so we don't deny cycles to other parts of the process when lots of
   // timers have been set.
@@ -170,11 +203,10 @@ bool TimerManager::RunSomePendingTimers() {
     // the TopTimer.  We'll execute the timer task only after the timer queue
     // is back in a consistent state.
     Timer* pending = timers_.top();
-
     // If pending task isn't invoked_later, then it must be possible to run it
     // now (i.e., current task needs to be reentrant).
     // TODO(jar): We may block tasks that we can queue from being popped.
-    if (!message_loop_->NestableTasksAllowed() &&
+    if (!message_loop()->NestableTasksAllowed() &&
         !pending->task()->is_owned_by_message_loop())
       break;
 
@@ -187,12 +219,12 @@ bool TimerManager::RunSomePendingTimers() {
       timers_.push(pending);
     }
 
-    message_loop_->RunTimerTask(pending);
+    message_loop()->RunTimerTask(pending);
   }
 
   // Restart the WM_TIMER (if necessary).
   if (did_work)
-    DidChangeNextTimer();
+    UpdateWindowsWmTimer();
 
   return did_work;
 }
@@ -207,30 +239,77 @@ void TimerManager::StartTimer(Timer* timer) {
 
   timers_.push(timer);  // Priority queue will sort the timer into place.
 
-  if (timers_.top() == timer)  // We are new head of queue.
-    DidChangeNextTimer();
+  if (timers_.top() == timer)
+    UpdateWindowsWmTimer();  // We are new head of queue.
+}
+
+void TimerManager::UpdateWindowsWmTimer() {
+  if (!use_native_timers_)
+    return;
+
+  if (timers_.empty()) {
+    KillTimer(GetMessageHWND(), reinterpret_cast<UINT_PTR>(this));
+    return;
+  }
+
+  int delay = GetCurrentDelay();
+  if (delay < USER_TIMER_MINIMUM)
+    delay = USER_TIMER_MINIMUM;
+
+  // Simulates malfunctioning, early firing timers. Pending tasks should
+  // only be invoked when the delay they specify has elapsed.
+  if (use_broken_delay_)
+    delay = 10;
+
+  // Create a WM_TIMER event that will wake us up to check for any pending
+  // timers (in case the message loop was otherwise starving us).
+  SetTimer(GetMessageHWND(), reinterpret_cast<UINT_PTR>(this), delay, NULL);
 }
 
 int TimerManager::GetCurrentDelay() {
   if (timers_.empty())
     return -1;
-  int delay = timers_.top()->GetCurrentDelay();
+  int delay = timers_.top()->current_delay();
   if (delay < 0)
     delay = 0;
   return delay;
 }
 
-void TimerManager::DidChangeNextTimer() {
-  // Determine if the next timer expiry actually changed...
-  if (!timers_.empty()) {
-    const Time& expiry = timers_.top()->fire_time();
-    if (expiry == next_timer_expiry_)
-      return;
-    next_timer_expiry_ = expiry;
-  } else {
-    next_timer_expiry_ = Time();
+int TimerManager::MessageWndProc(HWND hwnd, UINT message, WPARAM wparam,
+                                 LPARAM lparam) {
+  DCHECK(!lparam);
+  DCHECK(this == message_loop()->timer_manager());
+  if (message_loop()->NestableTasksAllowed())
+    RunSomePendingTimers();
+  else
+    UpdateWindowsWmTimer();
+  return 0;
+}
+
+MessageLoop* TimerManager::message_loop() {
+  if (!message_loop_)
+    message_loop_ = MessageLoop::current();
+  DCHECK(message_loop_ == MessageLoop::current());
+  return message_loop_;
+}
+
+
+HWND TimerManager::GetMessageHWND() {
+  if (!message_hwnd_) {
+    HINSTANCE hinst = GetModuleHandle(NULL);
+
+    WNDCLASSEX wc = {0};
+    wc.cbSize = sizeof(wc);
+    wc.lpfnWndProc = ::MessageWndProc;
+    wc.hInstance = hinst;
+    wc.lpszClassName = kWndClass;
+    RegisterClassEx(&wc);
+
+    message_hwnd_ = CreateWindow(kWndClass, 0, 0, 0, 0, 0, 0, HWND_MESSAGE, 0,
+                                 hinst, 0);
+    DCHECK(message_hwnd_);
   }
-  message_loop_->DidChangeNextTimerExpiry();
+  return message_hwnd_;
 }
 
 //-----------------------------------------------------------------------------
diff --git a/base/timer.h b/base/timer.h
index c23f725..de22b64 100644
--- a/base/timer.h
+++ b/base/timer.h
@@ -30,50 +30,54 @@
 #ifndef BASE_TIMER_H_
 #define BASE_TIMER_H_
 
+#include <math.h>
+
 #include <queue>
 #include <vector>
 
 #include "base/basictypes.h"
 #include "base/time.h"
 
-//-----------------------------------------------------------------------------
+#ifdef OS_WIN
+#include <windows.h>
+#endif  // OS_WIN
+
 // Timer/TimerManager are objects designed to help setting timers.
 // Goals of TimerManager:
-// - have only one system timer for all app timer functionality
+// - have only one Windows system timer for all app timer functionality
 // - work around bugs with timers firing arbitrarily earlier than specified
 // - provide the ability to run timers even if the application is in a
 //   windows modal app loop.
-//-----------------------------------------------------------------------------
 
-class MessageLoop;
 class TimerManager;
 class Task;
+class MessageLoop;
 
-//-----------------------------------------------------------------------------
-// The core timer object.  Use TimerManager to create and control timers.
 class Timer {
  public:
   Timer(int delay, Task* task, bool repeating);
 
-  // The task to be run when the timer fires.
   Task* task() const { return task_; }
   void set_task(Task* task) { task_ = task; }
 
-  // Returns the time in msec relative to now that the timer should fire.
-  int GetCurrentDelay() const;
+  int current_delay() const {
+    // Be careful here.  Timers have a precision of microseconds,
+    // but this API is in milliseconds.  If there are 5.5ms left,
+    // should the delay be 5 or 6?  It should be 6 to avoid timers
+    // firing early.  Implement ceiling by adding 999us prior to
+    // conversion to ms.
+    double delay = ceil((fire_time_ - Time::Now()).InMillisecondsF());
+    return static_cast<int>(delay);
+  }
 
-  // Returns the absolute time at which the timer should fire.
   const Time &fire_time() const { return fire_time_; }
 
-  // A repeating timer is a timer that is automatically scheduled to fire again
-  // after it fires.
   bool repeating() const { return repeating_; }
 
   // Update (or fill in) creation_time_, and calculate future fire_time_ based
   // on current time plus delay_.
   void Reset();
 
-  // A unique identifier for this timer.
   int id() const { return timer_id_; }
 
  protected:
@@ -89,8 +93,9 @@ class Timer {
   // Timer delay in milliseconds.
   int delay_;
 
-  // A monotonically increasing timer id.  Used for ordering two timers which
-  // have the same timestamp in a FIFO manner.
+  // A monotonically increasing timer id.  Used
+  // for ordering two timers which have the same
+  // timestamp in a FIFO manner.
   int timer_id_;
 
   // Whether or not this timer repeats.
@@ -100,11 +105,9 @@ class Timer {
   // iteration started.)
   Time creation_time_;
 
-  DISALLOW_COPY_AND_ASSIGN(Timer);
+  DISALLOW_EVIL_CONSTRUCTORS(Timer);
 };
 
-//-----------------------------------------------------------------------------
-// Used to implement TimerPQueue
 class TimerComparison {
  public:
   bool operator() (const Timer* t1, const Timer* t2) const {
@@ -123,14 +126,14 @@ class TimerComparison {
   }
 };
 
-//-----------------------------------------------------------------------------
 // Subclass priority_queue to provide convenient access to removal from this
 // list.
 //
 // Terminology: The "pending" timer is the timer at the top of the queue,
 //              i.e. the timer whose task needs to be Run next.
-class TimerPQueue :
-    public std::priority_queue<Timer*, std::vector<Timer*>, TimerComparison> {
+class TimerPQueue : public std::priority_queue<Timer*,
+                                               std::vector<Timer*>,
+                                               TimerComparison> {
  public:
   // Removes |timer| from the queue.
   void RemoveTimer(Timer* timer);
@@ -139,26 +142,32 @@ class TimerPQueue :
   bool ContainsTimer(const Timer* timer) const;
 };
 
-//-----------------------------------------------------------------------------
-// There is one TimerManager per thread, owned by the MessageLoop.  Timers can
-// either be fired by the MessageLoop from within its run loop or via a system
-// timer event that the MesssageLoop constructs.  The advantage of the former
-// is that we can make timers fire significantly faster than the granularity
-// provided by the system.  The advantage of a system timer is that modal
-// message loops which don't run our MessageLoop code will still be able to
-// process system timer events.
+// There is one TimerManager per thread, owned by the MessageLoop.
+// Timers can either be fired directly by the MessageLoop, or by
+// SetTimer and a WM_TIMER message.  The advantage of the former
+// is that we can make timers fire significantly faster than the 10ms
+// granularity provided by SetTimer().  The advantage of SetTimer()
+// is that modal message loops which don't run our MessageLoop
+// code will still be able to process WM_TIMER messages.
 //
-// NOTE:  TimerManager is not thread safe.  You cannot set timers onto a thread
-//        other than your own.
+// Note:  TimerManager is not thread safe.  You cannot set timers
+//        onto a thread other than your own.
 class TimerManager {
  public:
-  explicit TimerManager(MessageLoop* message_loop);
+  TimerManager();
   ~TimerManager();
 
   // Create and start a new timer. |task| is owned by the caller, as is the
   // timer object that is returned.
   Timer* StartTimer(int delay, Task* task, bool repeating);
 
+  // Flag indicating whether the timer manager should use the OS
+  // timers or not.  Default is true.  MessageLoops which are not reliably
+  // called due to nested windows message loops should set this to
+  // true.
+  bool use_native_timers() { return use_native_timers_; }
+  void set_use_native_timers(bool value) { use_native_timers_ = value; }
+
   // Starts a timer.  This is a no-op if the timer is already started.
   void StartTimer(Timer* timer);
 
@@ -181,6 +190,15 @@ class TimerManager {
   // pqueue) needs to be fired. Returns -1 if no timers are pending.
   int GetCurrentDelay();
 
+  // A handler for WM_TIMER messages.
+  // If a task is not running currently, it runs some timer tasks (if there are
+  // some ready to fire), otherwise it just updates the WM_TIMER to be called
+  // again (hopefully when it is allowed to run a task).
+  int MessageWndProc(HWND hwnd, UINT message, WPARAM wparam, LPARAM lparam);
+
+  // Return cached copy of MessageLoop::current().
+  MessageLoop* message_loop();
+
 #ifdef UNIT_TEST
   // For testing only, used to simulate broken early-firing WM_TIMER
   // notifications by setting arbitrarily small delays in SetTimer.
@@ -189,33 +207,35 @@ class TimerManager {
   }
 #endif  // UNIT_TEST
 
-  bool use_broken_delay() const {
-    return use_broken_delay_;
-  }
-
  protected:
   // Peek at the timer which will fire soonest.
   Timer* PeekTopTimer();
 
  private:
-  void DidChangeNextTimer();
+  // Update our Windows WM_TIMER to match our most immediately pending timer.
+  void UpdateWindowsWmTimer();
+
+#ifdef OS_WIN
+  // Retrieve the Message Window that handles WM_TIMER messages from the
+  // system.
+  HWND GetMessageHWND();
 
-  // A cached value that indicates the time when we think the next timer is to
-  // fire.  We use this to determine if we should call DidChangeNextTimerExpiry
-  // on the MessageLoop.
-  Time next_timer_expiry_;
+  HWND message_hwnd_;
+#endif  // OS_WIN
 
   TimerPQueue timers_;
 
   bool use_broken_delay_;
 
+  // Flag to enable/disable use of native timers.
+  bool use_native_timers_;
+
   // A lazily cached copy of MessageLoop::current.
   MessageLoop* message_loop_;
 
-  DISALLOW_COPY_AND_ASSIGN(TimerManager);
+  DISALLOW_EVIL_CONSTRUCTORS(TimerManager);
 };
 
-//-----------------------------------------------------------------------------
 // A simple wrapper for the Timer / TimerManager API.  This is a helper class.
 // Use OneShotTimer or RepeatingTimer instead.
 class SimpleTimer {
@@ -261,10 +281,9 @@ class SimpleTimer {
   // we are deallocated. Defaults to true.
   bool owns_task_;
 
-  DISALLOW_COPY_AND_ASSIGN(SimpleTimer);
+  DISALLOW_EVIL_CONSTRUCTORS(SimpleTimer);
 };
 
-//-----------------------------------------------------------------------------
 // A simple, one-shot timer.  The task is run after the specified delay once
 // the Start method is called.  The task is deleted when the timer object is
 // destroyed.
@@ -279,10 +298,9 @@ class OneShotTimer : public SimpleTimer {
       : SimpleTimer(delay, task, false) {
   }
  private:
-  DISALLOW_COPY_AND_ASSIGN(OneShotTimer);
+  DISALLOW_EVIL_CONSTRUCTORS(OneShotTimer);
 };
 
-//-----------------------------------------------------------------------------
 // A simple, repeating timer.  The task is run at the specified interval once
 // the Start method is called.  The task is deleted when the timer object is
 // destroyed.
@@ -297,7 +315,7 @@ class RepeatingTimer : public SimpleTimer {
       : SimpleTimer(interval, task, true) {
   }
  private:
-  DISALLOW_COPY_AND_ASSIGN(RepeatingTimer);
+  DISALLOW_EVIL_CONSTRUCTORS(RepeatingTimer);
 };
 
 #endif  // BASE_TIMER_H_
diff --git a/base/timer_unittest.cc b/base/timer_unittest.cc
index 4c2593f..814836b 100644
--- a/base/timer_unittest.cc
+++ b/base/timer_unittest.cc
@@ -295,9 +295,6 @@ TEST(TimerTest, FifoOrder) {
 
   class MockTimerManager : public TimerManager {
    public:
-    MockTimerManager() : TimerManager(MessageLoop::current()) {
-    }
-    
     // Pops the most-recent to fire timer and returns its timer id.
     // Returns -1 if there are no timers in the list.
     int pop() {
diff --git a/base/tracked_objects.cc b/base/tracked_objects.cc
index f94d77b..8694bfd 100644
--- a/base/tracked_objects.cc
+++ b/base/tracked_objects.cc
@@ -29,8 +29,6 @@
 
 #include "base/tracked_objects.h"
 
-#include <math.h>
-
 #include "base/string_util.h"
 
 namespace tracked_objects {
diff --git a/chrome/common/slide_animation.cc b/chrome/common/slide_animation.cc
index 2be6d093..f3f9c5a 100644
--- a/chrome/common/slide_animation.cc
+++ b/chrome/common/slide_animation.cc
@@ -29,8 +29,6 @@
 
 #include "chrome/common/slide_animation.h"
 
-#include <math.h>
-
 // How many frames per second to target.
 static const int kDefaultFramerateHz = 50;