Implement system tracing for cros

content/browser/tracing/tracing_ui.h

Index: content/browser/tracing/tracing_ui.h
diff --git a/content/browser/tracing/tracing_ui.h b/content/browser/tracing/tracing_ui.h
index 40ce0821e2d49a05711cadc43c8ea8900a0e37b5..58db8473e316315e282fa4b22c09f7623c37d938 100644
--- a/content/browser/tracing/tracing_ui.h
+++ b/content/browser/tracing/tracing_ui.h
@@ -5,6 +5,7 @@
 #ifndef CONTENT_BROWSER_TRACING_UI_H_
 #define CONTENT_BROWSER_TRACING_UI_H_
 
+#include "base/memory/ref_counted_memory.h"
 #include "content/public/browser/web_ui_controller.h"
 
 namespace content {
@@ -15,6 +16,8 @@ class CONTENT_EXPORT TracingUI : public WebUIController {
   explicit TracingUI(WebUI* web_ui);
   virtual ~TracingUI();
   void OnMonitoringStateChanged(bool is_monitoring);
+  void OnSystemTraceDataCollected(
+      const scoped_refptr<base::RefCountedString>& events_str_ptr);
 
  private:
   DISALLOW_COPY_AND_ASSIGN(TracingUI);