Grab input after toplevel screen locker window is shown.

chrome/browser/chromeos/login/screen_locker.cc

Index: chrome/browser/chromeos/login/screen_locker.cc
diff --git a/chrome/browser/chromeos/login/screen_locker.cc b/chrome/browser/chromeos/login/screen_locker.cc
index 7b4d6b55200a7adabc985ec7099fce3bad7fd623..49c0910d9f20ef2717b31cfe93ebe87cfe38f0a5 100644
--- a/chrome/browser/chromeos/login/screen_locker.cc
+++ b/chrome/browser/chromeos/login/screen_locker.cc
@@ -583,8 +583,6 @@ void ScreenLocker::Init() {
         new GrabWidgetRootView(screen_lock_view_));
   }
 
-  lock_widget_->Show();
-
   // Configuring the background url.
   std::string url_string =
       CommandLine::ForCurrentProcess()->GetSwitchValueASCII(
@@ -604,6 +602,10 @@ void ScreenLocker::Init() {
   lock_window_->SetContentsView(background_view_);
   lock_window_->Show();
 
+  // Show lock_widget after the lock_window is shown so that
+  // we can grab inputs immediately.
+  lock_widget_->Show();
+
   // Don't let X draw default background, which was causing flash on
   // resume.
   gdk_window_set_back_pixmap(lock_window_->GetNativeView()->window,