High resolution timer fix for Windows

base/message_loop/message_pump_win.cc

Index: base/message_loop/message_pump_win.cc
diff --git a/base/message_loop/message_pump_win.cc b/base/message_loop/message_pump_win.cc
index ae022bf0957f48be47ad16c77b0f0d99693add21..56288f20f24a6ecaf2316f84594956956c89dcbb 100644
--- a/base/message_loop/message_pump_win.cc
+++ b/base/message_loop/message_pump_win.cc
@@ -269,6 +269,13 @@ void MessagePumpForUI::WaitForWork() {
   if (delay < 0)  // Negative value means no timers waiting.
     delay = INFINITE;
 
+  // The delegate will crank the systemwide timer resolution if needed.
+  // Note that the |delay| value is not enough of an indicator if we need to
+  // to so. For example, imagine a 30 seconds delayed task that we only get
+  // arround to service 5ms before the deadline. Should we crank up the
+  // systemwide timer? no. A 30s timer can be fired 15ms later.
+  state_->delegate->UpdateTimerGranularity();
+
   DWORD result;
   result = MsgWaitForMultipleObjectsEx(0, NULL, delay, QS_ALLINPUT,
                                        MWMO_INPUTAVAILABLE);
@@ -529,6 +536,9 @@ void MessagePumpForIO::WaitForWork() {
   // recursion problems.
   DCHECK_EQ(1, state_->run_depth) << "Cannot nest an IO message loop!";
 
+  // See the comment in MessagePumpForUI::WaitForWork().
+  state_->delegate->UpdateTimerGranularity();
+
   int timeout = GetCurrentDelay();
   if (timeout < 0)  // Negative value means no timers waiting.
     timeout = INFINITE;