Add a full screen virtual keyboard to virtual keyboard root window

ash/shell.h

Index: ash/shell.h
diff --git a/ash/shell.h b/ash/shell.h
index 62379acd06aebdf01ca5cf0c590760ce59ca0171..81691045e45c13df6ef4a62243af7251beaa69ea 100644
--- a/ash/shell.h
+++ b/ash/shell.h
@@ -270,6 +270,9 @@ class ASH_EXPORT Shell
   // Called when the user logs in.
   void OnLoginStateChanged(user::LoginStatus status);
 
+  // Called after the logged-in user's profile is ready.
+  void OnLoginUserProfilePrepared();
+
   // Called when the login status changes.
   // TODO(oshima): Investigate if we can merge this and |OnLoginStateChanged|.
   void UpdateAfterLoginStatusChange(user::LoginStatus status);
@@ -284,6 +287,10 @@ class ASH_EXPORT Shell
   // Initializes |launcher_|.  Does nothing if it's already initialized.
   void CreateLauncher();
 
+  // Creates virtual keyboard. Deletes the old virtual keyboard if it's already
+  // exist.
+  void CreateKeyboard();
+
   // Show shelf view if it was created hidden (before session has started).
   void ShowLauncher();