Fix cpu/memory measurements on OS X.

base/trace_event.cc

Index: base/trace_event.cc
diff --git a/base/trace_event.cc b/base/trace_event.cc
index 13c0c2cd82213df237a8801f65240c60a437f098..ff834eafcecbdc7c76e307447c9d6601d5dc4ab6 100644
--- a/base/trace_event.cc
+++ b/base/trace_event.cc
@@ -29,7 +29,14 @@ static const FilePath::CharType* kLogFileName =
 
 TraceLog::TraceLog() : enabled_(false), log_file_(NULL) {
   base::ProcessHandle proc = base::GetCurrentProcessHandle();
+#if !defined(OS_MACOSX)
   process_metrics_.reset(base::ProcessMetrics::CreateProcessMetrics(proc));
+#else
+  // The default port provider is sufficient to get data for the current
+  // process.
+  process_metrics_.reset(base::ProcessMetrics::CreateProcessMetrics(proc,
+                                                                    NULL));
+#endif
 }
 
 TraceLog::~TraceLog() {