Fixing the bug, that caused UI to hang after unsupported device was inserted.

chrome/browser/idle_mac.mm

 // Copyright (c) 2009 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.
 
 #import "chrome/browser/idle.h"
 
 #import <Cocoa/Cocoa.h>
 #import <CoreGraphics/CGEventSource.h>
 
 @interface MacScreenMonitor : NSObject {
@@ skipping 67 matching lines @@
   if (!g_screenMonitor)
     g_screenMonitor = [[MacScreenMonitor alloc] init];
 }
 
 void StopIdleMonitor() {
   [g_screenMonitor release];
   g_screenMonitor = nil;
 }
 
 void CalculateIdleState(unsigned int idle_threshold, IdleCallback notify) {
-  if ([g_screenMonitor isScreensaverRunning] ||
-      [g_screenMonitor isScreenLocked]) {
+  if (CheckIdleStateIsLocked()) {
     notify.Run(IDLE_STATE_LOCKED);
     return;
   }
 
   CFTimeInterval idle_time = CGEventSourceSecondsSinceLastEventType(
       kCGEventSourceStateCombinedSessionState,
       kCGAnyInputEventType);
   if (idle_time >= idle_threshold)
     notify.Run(IDLE_STATE_IDLE);
   else
     notify.Run(IDLE_STATE_ACTIVE);
 }
+
+bool CheckIdleStateIsLocked() {
+  return [g_screenMonitor isScreensaverRunning] ||
+      [g_screenMonitor isScreenLocked];
+}