(Merge to M-51) Revise the shelf alignment locking mechanism.

ash/system/user/tray_user.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ash/system/user/tray_user.h"
 
 #include "ash/ash_switches.h"
 #include "ash/root_window_controller.h"
 #include "ash/session/session_state_delegate.h"
 #include "ash/shelf/shelf_layout_manager.h"
+#include "ash/shelf/shelf_util.h"
 #include "ash/shell_delegate.h"
 #include "ash/system/tray/system_tray.h"
 #include "ash/system/tray/system_tray_delegate.h"
 #include "ash/system/tray/system_tray_notifier.h"
 #include "ash/system/tray/tray_constants.h"
 #include "ash/system/tray/tray_item_view.h"
 #include "ash/system/tray/tray_utils.h"
 #include "ash/system/user/rounded_image_view.h"
 #include "ash/system/user/user_view.h"
 #include "base/logging.h"
@@ skipping 163 matching lines @@
   UpdateAvatarImage(status);
 
   // Update layout after setting label_ and avatar_ with new login status.
   UpdateLayoutOfItem();
 }
 
 void TrayUser::UpdateAfterShelfAlignmentChange(ShelfAlignment alignment) {
   // Inactive users won't have a layout.
   if (!layout_view_)
     return;
-  if (alignment == SHELF_ALIGNMENT_BOTTOM) {
+  if (IsHorizontalAlignment(alignment)) {
     if (avatar_) {
       avatar_->SetBorder(views::Border::NullBorder());
       avatar_->SetCornerRadii(
           0, kTrayAvatarCornerRadius, kTrayAvatarCornerRadius, 0);
     }
     if (label_) {
       // If label_ hasn't figured out its size yet, do that first.
       if (label_->GetContentsBounds().height() == 0)
         label_->SizeToPreferredSize();
       int height = label_->GetContentsBounds().height();
@@ skipping 63 matching lines @@
   // Unit tests might come here with no images for some users.
   if (avatar_->size().IsEmpty())
     avatar_->SetSize(gfx::Size(kTrayAvatarSize, kTrayAvatarSize));
 }
 
 void TrayUser::UpdateLayoutOfItem() {
   UpdateAfterShelfAlignmentChange(system_tray()->shelf_alignment());
 }
 
 }  // namespace ash