Update from https://crrev.com/327068

base/synchronization/waitable_event_win.cc

 // Copyright (c) 2011 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/synchronization/waitable_event.h"
 
-#include <math.h>
 #include <windows.h>
 
 #include "base/logging.h"
+#include "base/numerics/safe_conversions.h"
 #include "base/threading/thread_restrictions.h"
 #include "base/time/time.h"
 
 namespace base {
 
 WaitableEvent::WaitableEvent(bool manual_reset, bool signaled)
     : handle_(CreateEvent(NULL, manual_reset, signaled, NULL)) {
   // We're probably going to crash anyways if this is ever NULL, so we might as
   // well make our stack reports more informative by crashing here.
   CHECK(handle_.IsValid());
 }
 
 WaitableEvent::WaitableEvent(win::ScopedHandle handle)
     : handle_(handle.Pass()) {
   CHECK(handle_.IsValid()) << "Tried to create WaitableEvent from NULL handle";
 }
 
 WaitableEvent::~WaitableEvent() {
 }
 
 void WaitableEvent::Reset() {
   ResetEvent(handle_.Get());
 }
 
 void WaitableEvent::Signal() {
   SetEvent(handle_.Get());
 }
 
 bool WaitableEvent::IsSignaled() {
-  return TimedWait(TimeDelta::FromMilliseconds(0));
+  return TimedWait(TimeDelta());
 }
 
 void WaitableEvent::Wait() {
   base::ThreadRestrictions::AssertWaitAllowed();
   DWORD result = WaitForSingleObject(handle_.Get(), INFINITE);
   // It is most unexpected that this should ever fail.  Help consumers learn
   // about it if it should ever fail.
   DCHECK_EQ(WAIT_OBJECT_0, result) << "WaitForSingleObject failed";
 }
 
 bool WaitableEvent::TimedWait(const TimeDelta& max_time) {
   base::ThreadRestrictions::AssertWaitAllowed();
-  DCHECK(max_time >= TimeDelta::FromMicroseconds(0));
-  // Be careful here.  TimeDelta has 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 returning too early.
-  double timeout = ceil(max_time.InMillisecondsF());
-  DWORD result = WaitForSingleObject(handle_.Get(),
-                                     static_cast<DWORD>(timeout));
+  DCHECK_GE(max_time, TimeDelta());
+  // Truncate the timeout to milliseconds. The API specifies that this method
+  // can return in less than |max_time| (when returning false), as the argument
+  // is the maximum time that a caller is willing to wait.
+  DWORD timeout = saturated_cast<DWORD>(max_time.InMilliseconds());
+
+  DWORD result = WaitForSingleObject(handle_.Get(), timeout);
   switch (result) {
     case WAIT_OBJECT_0:
       return true;
     case WAIT_TIMEOUT:
       return false;
   }
   // It is most unexpected that this should ever fail.  Help consumers learn
   // about it if it should ever fail.
   NOTREACHED() << "WaitForSingleObject failed";
   return false;
@@ skipping 17 matching lines @@
                              INFINITE);  // no timeout
   if (result >= WAIT_OBJECT_0 + count) {
     DPLOG(FATAL) << "WaitForMultipleObjects failed";
     return 0;
   }
 
   return result - WAIT_OBJECT_0;
 }
 
 }  // namespace base