content: Increase thread priority for display critical IO threads on ChromeOS.

content/browser/browser_main_loop.cc

 // Copyright (c) 2012 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/browser_main_loop.h"
 
 #include <stddef.h>
 #include <utility>
 
 #include "base/bind.h"
@@ skipping 866 matching lines @@
         options = io_message_loop_options;
 #endif  // defined(OS_WIN)
         options.timer_slack = base::TIMER_SLACK_MAXIMUM;
         break;
       case BrowserThread::IO:
         TRACE_EVENT_BEGIN1("startup",
             "BrowserMainLoop::CreateThreads:start",
             "Thread", "BrowserThread::IO");
         thread_to_start = &io_thread_;
         options = io_message_loop_options;
-#if defined(OS_ANDROID)
+#if defined(OS_ANDROID) || defined(OS_CHROMEOS)
         // Up the priority of the |io_thread_| as some of its IPCs relate to
         // display tasks.
         options.priority = base::ThreadPriority::DISPLAY;
 #endif
         break;
       case BrowserThread::UI:
       case BrowserThread::ID_COUNT:
       default:
         NOTREACHED();
         break;
@@ skipping 565 matching lines @@
   DCHECK(is_tracing_startup_for_duration_);
 
   is_tracing_startup_for_duration_ = false;
   TracingController::GetInstance()->StopTracing(
       TracingController::CreateFileSink(
           startup_trace_file_,
           base::Bind(OnStoppedStartupTracing, startup_trace_file_)));
 }
 
 }  // namespace content