Chrome tracing for system-wide performance stats.

content/browser/browser_main_loop.cc

Index: content/browser/browser_main_loop.cc
diff --git a/content/browser/browser_main_loop.cc b/content/browser/browser_main_loop.cc
index 429da81500747d7355ae5e8ed989748e2d582bef..85a53ab9fab1953d4fb465eb5ace14591a3e944e 100644
--- a/content/browser/browser_main_loop.cc
+++ b/content/browser/browser_main_loop.cc
@@ -495,6 +495,9 @@ void BrowserMainLoop::MainMessageLoopStart() {
       ::HeapProfilerStop,
       ::GetHeapProfile));
 #endif
+
+  system_stats_monitor_.reset(new base::debug::TraceEventSystemStatsMonitor(
+      base::MessageLoop::current()->message_loop_proxy()));

[darin (slow to review), 2013/09/12 20:51:15]

nit: New code should really be using base::ThreadTaskRunnerHandle. That works
much the same way as MessageLoopProxy so it should be a simple change for this
CL.

[jwmak, 2013/09/13 20:57:11]

Done.

 }
 
 int BrowserMainLoop::PreCreateThreads() {
@@ -715,6 +718,7 @@ void BrowserMainLoop::ShutdownThreadsAndCleanUp() {
   }
 
   trace_memory_controller_.reset();
+  system_stats_monitor_.reset();
 
 #if !defined(OS_IOS)
   // Destroying the GpuProcessHostUIShims on the UI thread posts a task to