Add instrumentation to the MessagePumpMac family of classes.

base/message_loop/message_loop.cc

 // Copyright 2013 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/message_loop.h"
 
 #include <algorithm>
 
 #include "base/bind.h"
 #include "base/compiler_specific.h"
@@ skipping 638 matching lines @@
 bool MessageLoop::DoIdleWork() {
   if (ProcessNextDelayedNonNestableTask())
     return true;
 
   if (run_loop_->quit_when_idle_received_)
     pump_->Quit();
 
   return false;
 }
 
+void MessageLoop::GetQueueingInformation(size_t* queue_size,
+                                         TimeDelta* queueing_delay) {
+  size_t size = work_queue_.size();
+  if (queue_size)

[Mark Mentovai, 2013/08/22 18:00:12]

Since nobody needs to call this with NULL arguments, you can get rid of the code
that lets the arguments be NULL, and just document that both arguments are
required. That will let you clean up the logic in this function in a way that
will make the block on lines 665-669 substantially more readable.

[Robert Sesek, 2013/08/22 19:12:21]

Done.

+    *queue_size = size + delayed_work_queue_.size();
+
+  if (size == 0 || !queueing_delay) {
+    if (queueing_delay)
+      *queueing_delay = TimeDelta();
+    return;
+  }
+
+  const PendingTask& next_to_run = work_queue_.front();
+  tracked_objects::Duration duration =
+      tracked_objects::TrackedTime::Now() - next_to_run.EffectiveTimePosted();
+  *queueing_delay = TimeDelta::FromMilliseconds(duration.InMilliseconds());
+}
+
 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) {
@@ skipping 76 matching lines @@
       fd,
       persistent,
       mode,
       controller,
       delegate);
 }
 
 #endif
 
 }  // namespace base