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

content/browser/devtools/protocol/tracing_handler.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/browser/devtools/protocol/tracing_handler.h"
 
 #include <cmath>
 
 #include "base/bind.h"
 #include "base/debug/trace_event_impl.h"
@@ skipping 124 matching lines @@
                  weak_factory_.GetWeakPtr(),
                  command));
   return command->AsyncResponsePromise();
 }
 
 void TracingHandler::OnRecordingEnabled(
     scoped_refptr<DevToolsProtocol::Command> command) {
   client_->SendStartResponse(command, StartResponse::Create());
 }
 
-void TracingHandler::OnBufferUsage(float usage) {
-  client_->BufferUsage(BufferUsageParams::Create()->set_value(usage));
+void TracingHandler::OnBufferUsage(float percent_full,
+                                   size_t approximate_event_count) {
+  client_->BufferUsage(BufferUsageParams::Create()->set_value(percent_full));
 }
 
 void TracingHandler::OnCategoriesReceived(
     scoped_refptr<DevToolsProtocol::Command> command,
     const std::set<std::string>& category_set) {
   std::vector<std::string> categories;
   for (const std::string& category : category_set)
     categories.push_back(category);
   client_->SendGetCategoriesResponse(command,
       GetCategoriesResponse::Create()->set_categories(categories));
@@ skipping 25 matching lines @@
 
 void TracingHandler::SetupTimer(double usage_reporting_interval) {
   if (usage_reporting_interval == 0) return;
 
   if (usage_reporting_interval < kMinimumReportingInterval)
       usage_reporting_interval = kMinimumReportingInterval;
 
   base::TimeDelta interval = base::TimeDelta::FromMilliseconds(
       std::ceil(usage_reporting_interval));
   buffer_usage_poll_timer_.reset(new base::Timer(
-      FROM_HERE,
-      interval,
-      base::Bind(
-          base::IgnoreResult(&TracingController::GetTraceBufferPercentFull),
-          base::Unretained(TracingController::GetInstance()),
-          base::Bind(&TracingHandler::OnBufferUsage,
-                     weak_factory_.GetWeakPtr())),
+      FROM_HERE, interval,
+      base::Bind(base::IgnoreResult(&TracingController::GetTraceBufferUsage),
+                 base::Unretained(TracingController::GetInstance()),
+                 base::Bind(&TracingHandler::OnBufferUsage,
+                            weak_factory_.GetWeakPtr())),
       true));
   buffer_usage_poll_timer_->Reset();
 }
 
 void TracingHandler::DisableRecording(bool abort) {
   is_recording_ = false;
   buffer_usage_poll_timer_.reset();
   TracingController::GetInstance()->DisableRecording(
       abort ? nullptr : new DevToolsTraceSinkProxy(weak_factory_.GetWeakPtr()));
 }
 
 }  // namespace tracing
 }  // namespace devtools
 }  // namespace content