Add instrumentation to the MessagePumpMac family of classes.

base/message_loop/message_loop.cc

Index: base/message_loop/message_loop.cc
diff --git a/base/message_loop/message_loop.cc b/base/message_loop/message_loop.cc
index 826c7573ee60e942fd0fb1beac5dff327d7a907c..84b380d7aa34ef9aa8d73789d702db49dc2b6165 100644
--- a/base/message_loop/message_loop.cc
+++ b/base/message_loop/message_loop.cc
@@ -656,6 +656,24 @@ bool MessageLoop::DoIdleWork() {
   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) {