Removing file_thread_task_runner parameter from SerialIoHandler

content/browser/tracing/power_tracing_agent.cc

Index: content/browser/tracing/power_tracing_agent.cc
diff --git a/content/browser/tracing/power_tracing_agent.cc b/content/browser/tracing/power_tracing_agent.cc
index b4887fc1c4e79b804243449c3f142b59b972a298..6276c099cec05810a290a360cfaf74f5f08dad0f 100644
--- a/content/browser/tracing/power_tracing_agent.cc
+++ b/content/browser/tracing/power_tracing_agent.cc
@@ -69,8 +69,7 @@ void PowerTracingAgent::StartAgentTracingOnIOThread(
   DCHECK_CURRENTLY_ON(BrowserThread::IO);
 
   battor_agent_.reset(new battor::BattOrAgent(
-      path, this, BrowserThread::GetTaskRunnerForThread(BrowserThread::FILE),
-      BrowserThread::GetTaskRunnerForThread(BrowserThread::UI)));
+      path, this, BrowserThread::GetTaskRunnerForThread(BrowserThread::UI)));
 
   start_tracing_callback_ = callback;
   battor_agent_->StartTracing();