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

chrome/browser/idle_mac.mm

Index: chrome/browser/idle_mac.mm
diff --git a/chrome/browser/idle_mac.mm b/chrome/browser/idle_mac.mm
index e1ab476dc12484558218c0ccb1932dc48938659e..b1c30941a55a7b22d75b67d467ac63d51e6fa739 100644
--- a/chrome/browser/idle_mac.mm
+++ b/chrome/browser/idle_mac.mm
@@ -85,8 +85,7 @@ void StopIdleMonitor() {
 }
 
 void CalculateIdleState(unsigned int idle_threshold, IdleCallback notify) {
-  if ([g_screenMonitor isScreensaverRunning] ||
-      [g_screenMonitor isScreenLocked]) {
+  if (CheckIdleStateIsLocked()) {
     notify.Run(IDLE_STATE_LOCKED);
     return;
   }
@@ -99,3 +98,8 @@ void CalculateIdleState(unsigned int idle_threshold, IdleCallback notify) {
   else
     notify.Run(IDLE_STATE_ACTIVE);
 }
+
+bool CheckIdleStateIsLocked() {
+  return [g_screenMonitor isScreensaverRunning] ||
+      [g_screenMonitor isScreenLocked];
+}