Pass login-manager switch value to login wizard to determine which screen to
start with.
Refactored LoginObserver to ScreenObserver that could be used by other
screens as well.

BUG=34716
TEST=Currently there just should be no regression for Chrome based login
manager.
Review URL: http://codereview.chromium.org/574014

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@38297 0039d316-1c4b-4281-b951-d872f2087c98
diff --git a/chrome/chrome_browser.gypi b/chrome/chrome_browser.gypi
index 7be4f86..8390e30fe 100755
--- a/chrome/chrome_browser.gypi
+++ b/chrome/chrome_browser.gypi
@@ -299,6 +299,7 @@
         'browser/chromeos/login/login_manager_view.h',
         'browser/chromeos/login/login_wizard_view.cc',
         'browser/chromeos/login/login_wizard_view.h',
+        'browser/chromeos/login/screen_observer.h',
         'browser/chromeos/login/user_manager.cc',
         'browser/chromeos/login/user_manager.h',
         'browser/chromeos/main_menu.cc',