Screen Locker: 1st step
 * ScreenLocker screen currently reuses Background from Login screen.
 * GrabWidget is created to grab keyboard/mouse events.
 * Modified StubAuthentiator to fail when an empty password is entered.
 * Changed UserManager to explicitly remember the currently logged in user.
UI is not hooked yet.

BUG=43131, http://crosbug.com/2914
TEST=none

Review URL: http://codereview.chromium.org/1897001

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@46442 0039d316-1c4b-4281-b951-d872f2087c98
diff --git a/chrome/chrome_browser.gypi b/chrome/chrome_browser.gypi
index b1a32ad..892a048 100644
--- a/chrome/chrome_browser.gypi
+++ b/chrome/chrome_browser.gypi
@@ -410,6 +410,10 @@
         'browser/chromeos/login/network_screen_delegate.h',
         'browser/chromeos/login/rounded_rect_painter.cc',
         'browser/chromeos/login/rounded_rect_painter.h',
+        'browser/chromeos/login/screen_locker.cc',
+        'browser/chromeos/login/screen_locker.h',
+        'browser/chromeos/login/screen_lock_view.cc',
+        'browser/chromeos/login/screen_lock_view.h',
         'browser/chromeos/login/screen_observer.h',
         'browser/chromeos/login/update_screen.cc',
         'browser/chromeos/login/update_screen.h',