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

base/debug/trace_event_impl.cc

Index: base/debug/trace_event_impl.cc
diff --git a/base/debug/trace_event_impl.cc b/base/debug/trace_event_impl.cc
index ce62766da3df551884d487c2ea5f914a22f9d18a..45c8497a205057630a460b2ab02e23cf00308a76 100644
--- a/base/debug/trace_event_impl.cc
+++ b/base/debug/trace_event_impl.cc
@@ -1586,6 +1586,11 @@ bool TraceLog::HasEnabledStateObserver(EnabledStateObserver* listener) const {
   return it != enabled_state_observer_list_.end();
 }
 
+size_t TraceLog::GetBufferUsage() const {
+  AutoLock lock(lock_);
+  return logged_events_->Size();
+}
+
 float TraceLog::GetBufferPercentFull() const {
   AutoLock lock(lock_);
   return static_cast<float>(static_cast<double>(logged_events_->Size()) /