chromeos: Silence log spam from x11_util.cc.

chrome/browser/chrome_browser_main.cc

Index: chrome/browser/chrome_browser_main.cc
diff --git a/chrome/browser/chrome_browser_main.cc b/chrome/browser/chrome_browser_main.cc
index 46c9926416695b1ab9e563177179c345de2d0c0e..9b9b1ff2b85e876888b4048a613d1c1c7e246e5c 100644
--- a/chrome/browser/chrome_browser_main.cc
+++ b/chrome/browser/chrome_browser_main.cc
@@ -143,6 +143,7 @@
 #include "chrome/browser/chromeos/login/ownership_service.h"
 #include "chrome/browser/chromeos/login/screen_locker.h"
 #include "chrome/browser/chromeos/login/user_manager.h"
+#include "chrome/browser/chromeos/system/runtime_environment.h"
 #include "chrome/browser/chromeos/system_key_event_listener.h"
 #include "chrome/browser/chromeos/user_cros_settings_provider.h"
 #include "chrome/browser/chromeos/xinput_hierarchy_changed_event_listener.h"
@@ -1817,8 +1818,12 @@ int ChromeBrowserMainParts::PreMainMessageLoopRunInternal() {
   chromeos::AudioHandler::Initialize();
 
   // Listen for system key events so that the user will be able to adjust the
-  // volume on the login screen.
-  chromeos::SystemKeyEventListener::Initialize();
+  // volume on the login screen, if Chrome is running on Chrome OS
+  // (i.e. not Linux desktop), and in non-test mode.
+  if (chromeos::system::runtime_environment::IsRunningOnChromeOS() &&
+      !parameters().ui_task) {  // ui_task is non-NULL when running tests.
+    chromeos::SystemKeyEventListener::Initialize();
+  }
 
   // Listen for XI_HierarchyChanged events.
   chromeos::XInputHierarchyChangedEventListener::GetInstance();
@@ -2039,6 +2044,8 @@ void ChromeBrowserMainParts::PostMainMessageLoopRun() {
   // Singletons are finally destroyed in AtExitManager.
   chromeos::XInputHierarchyChangedEventListener::GetInstance()->Stop();
 
+  // chromeos::SystemKeyEventListener::Shutdown() is always safe to call,
+  // even if Initialize() wasn't called.
   chromeos::SystemKeyEventListener::Shutdown();
   chromeos::AudioHandler::Shutdown();
 #endif