Report trace buffer usage as number of events, not only percentage

base/debug/trace_event_impl.h

Index: base/debug/trace_event_impl.h
diff --git a/base/debug/trace_event_impl.h b/base/debug/trace_event_impl.h
index 6075e2dee78698a897ed2e5485d20a59de721edf..dc85c2cae011efd60c17543dadf9588dcdfe914c 100644
--- a/base/debug/trace_event_impl.h
+++ b/base/debug/trace_event_impl.h
@@ -495,7 +495,8 @@ class BASE_EXPORT TraceLog {
   void RemoveEnabledStateObserver(EnabledStateObserver* listener);
   bool HasEnabledStateObserver(EnabledStateObserver* listener) const;
 
-  float GetBufferPercentFull() const;
+  void GetBufferUsage(float* percent_full,

[caseq, 2014/11/13 17:16:21]

nit: we could probably keep several callsites less verbose if this were to
return struct { float percent full; size_t approximate_event_count; }.

[yurys, 2014/11/14 10:06:59]

Done.

+                      size_t* approximate_event_count) const;
   bool BufferIsFull() const;
 
   // Not using base::Callback because of its limited by 7 parameters.
@@ -603,7 +604,6 @@ class BASE_EXPORT TraceLog {
   static void DeleteForTesting();
 
   // Allow tests to inspect TraceEvents.
-  size_t GetEventsSize() const { return logged_events_->Size(); }
   TraceEvent* GetEventByHandle(TraceEventHandle handle);
 
   void SetProcessID(int process_id);