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

content/browser/browser_main_loop.cc

Index: content/browser/browser_main_loop.cc
diff --git a/content/browser/browser_main_loop.cc b/content/browser/browser_main_loop.cc
index 69dab775ebd5bfc469c4eb834f9b04305d23e9db..22c3e582f82b06dc0d1d2f72e5baf507e15ce85e 100644
--- a/content/browser/browser_main_loop.cc
+++ b/content/browser/browser_main_loop.cc
@@ -884,7 +884,7 @@ int BrowserMainLoop::CreateThreads() {
             "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;