chromeos: Fix shelf appearing at login screen under mash

chrome/browser/ui/ash/chrome_shell_delegate.cc

Index: chrome/browser/ui/ash/chrome_shell_delegate.cc
diff --git a/chrome/browser/ui/ash/chrome_shell_delegate.cc b/chrome/browser/ui/ash/chrome_shell_delegate.cc
index 2f1d12e8a0d13df9abd4f55fe091aab9a1190280..3dbe317b151378391f221023070d30f4480b27e9 100644
--- a/chrome/browser/ui/ash/chrome_shell_delegate.cc
+++ b/chrome/browser/ui/ash/chrome_shell_delegate.cc
@@ -563,7 +563,6 @@ void ChromeShellDelegate::Observe(int type,
       // chrome::NOTIFICATION_LOGIN_USER_PROFILE_PREPARED instead.
       if (shelf_delegate_)
         shelf_delegate_->OnUserProfileReadyToSwitch(profile);
-      ash::Shell::GetInstance()->OnLoginUserProfilePrepared();

[James Cook, 2016/12/16 01:28:27]

This is the core of the change. The shelf is created a little later, in response
to the session starting, using code that is the same in classic ash and mash.

       break;
     }
     case chrome::NOTIFICATION_SESSION_STARTED:
@@ -571,7 +570,6 @@ void ChromeShellDelegate::Observe(int type,
       // start.
       if (user_manager::UserManager::Get()->GetLoggedInUsers().size() < 2)
         InitAfterFirstSessionStart();
-      ash::WmShell::Get()->ShowShelf();
       break;
     default:
       NOTREACHED() << "Unexpected notification " << type;