Generate an ETW event at the end of "Complete" chrome://tracing events.

TraceEventETW export can export chrome://tracing events to ETW.
Unfortunately, the duration of "Complete" is not exported to ETW.

With this CL, an ETW event is exported at the end of "Complete"
chrome://tracing events.

The duration of a chrome://tracing "Complete" event can then be computed
by substracting the timestamp of the an ETW "Complete" event from the
timestamp of the corresponding ETW "Complete End" event.

Also, we can generate a "Region of Interest" in WPA for each "Complete"
event using this definition file (which we could distribute with
UIforETW):
https://drive.google.com/file/d/0B0CFRkIGz7pibWdzQUtpX2NUNGs/view?usp=sharing

BUG=546595

Review URL: https://codereview.chromium.org/1423663011

Cr-Commit-Position: refs/heads/master@{#357214}

1 files changed, 2 insertions, 11 deletions

diff --git a/base/trace_event/trace_event_etw_export_win.h b/base/trace_event/trace_event_etw_export_win.h
index 7a1c029..5c3ae60 100644
--- a/base/trace_event/trace_event_etw_export_win.h
+++ b/base/trace_event/trace_event_etw_export_win.h
@@ -49,17 +49,8 @@ class BASE_EXPORT TraceEventETWExport {
       const unsigned long long* arg_values,
       const scoped_refptr<ConvertableToTraceFormat>* convertable_values);
 
-  // Exports an event to ETW. This should be used when exporting an event only
-  // to ETW. Supports three arguments to be passed to ETW.
-  // TODO(georgesak): Allow different providers.
-  static void AddCustomEvent(const char* name,
-                             const char* phase,
-                             const char* arg_name_1,
-                             const char* arg_value_1,
-                             const char* arg_name_2,
-                             const char* arg_value_2,
-                             const char* arg_name_3,
-                             const char* arg_value_3);
+  // Exports an ETW event that marks the end of a complete event.
+  static void AddCompleteEndEvent(const char* name);
 
   // Returns true if any category in the group is enabled.
   static bool IsCategoryGroupEnabled(const char* category_group_name);