ash: Move shelf alignment and auto-hide calls from Shell to Shelf

ash/root_window_controller.cc

Index: ash/root_window_controller.cc
diff --git a/ash/root_window_controller.cc b/ash/root_window_controller.cc
index bf980dcc2ff36961962cf6cc04e9427e1abd021f..8135b83a5d07ac94a723c415704f9dd07a07f5ef 100644
--- a/ash/root_window_controller.cc
+++ b/ash/root_window_controller.cc
@@ -432,6 +432,11 @@ void RootWindowController::CreateShelf() {
   shelf_widget_->PostCreateShelf();
 }
 
+Shelf* RootWindowController::GetShelf() const {
+  // TODO(jamescook): Shelf should be owned by this class, not by ShelfWidget.
+  return shelf_widget_->shelf();
+}
+
 void RootWindowController::UpdateAfterLoginStatusChange(
     user::LoginStatus status) {
   if (status != user::LOGGED_IN_NONE)