Fixing "shelf confusion" with alignment

This is fixing the mentioned issue - however there are other issues which still need to be addressed (bigger refactor).

BUG=342232
TEST=visual

Review URL: https://codereview.chromium.org/740343005

Cr-Commit-Position: refs/heads/master@{#306016}

4 files changed, 23 insertions, 9 deletions

diff --git a/ash/shelf/shelf_layout_manager.cc b/ash/shelf/shelf_layout_manager.cc
index 178634c..340ab77 100644
--- a/ash/shelf/shelf_layout_manager.cc
+++ b/ash/shelf/shelf_layout_manager.cc
@@ -251,9 +251,15 @@ bool ShelfLayoutManager::SetAlignment(ShelfAlignment alignment) {
   if (alignment_ == alignment)
     return false;
 
-  // This should not be called during the lock screen transitions.
-  DCHECK(!Shell::GetInstance()->session_state_delegate()->IsScreenLocked());
   alignment_ = alignment;
+  if (Shell::GetInstance()->session_state_delegate()->IsScreenLocked()) {
+    // The shelf will itself move to the bottom while locked. If a request is
+    // sent to move while being locked, we postpone the move untill the lock
+    // screen goes away.
+    return false;
+  }
+
+  // This should not be called during the lock screen transitions.
   shelf_->SetAlignment(alignment);
   LayoutShelf();
   return true;
diff --git a/ash/shelf/shelf_layout_manager.h b/ash/shelf/shelf_layout_manager.h
index ac0c69d..bb3f34d 100644
--- a/ash/shelf/shelf_layout_manager.h
+++ b/ash/shelf/shelf_layout_manager.h
@@ -1,4 +1,4 @@
-// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Copyright 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.
 
@@ -90,9 +90,13 @@ class ASH_EXPORT ShelfLayoutManager
     return auto_hide_behavior_;
   }
 
-  // Sets the alignment. Returns true if the alignment is changed. Otherwise,
-  // returns false.
+  // Sets the alignment. Returns true if the alignment got changed. If nothing
+  // has visually be changed, false will be returned. This can happen if either
+  // the alignment was already set, or the shelf is currently locked and cannot
+  // be changed at this time. In the latter case the change will be performed
+  // once the shelf gets unlocked.
   bool SetAlignment(ShelfAlignment alignment);
+
   // Returns the desired alignment for the current state, either the user's
   // set alignment (alignment_) or SHELF_ALIGNMENT_BOTTOM when the screen
   // is locked.
diff --git a/ash/shelf/shelf_widget.cc b/ash/shelf/shelf_widget.cc
index 73bbeaa..ad9d6b6 100644
--- a/ash/shelf/shelf_widget.cc
+++ b/ash/shelf/shelf_widget.cc
@@ -1,4 +1,4 @@
-// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Copyright 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.
 
@@ -710,10 +710,12 @@ bool ShelfWidget::ShelfAlignmentAllowed() {
       Shell::GetInstance()->system_tray_delegate()->GetUserLoginStatus();
 
   switch (login_status) {
+    case user::LOGGED_IN_LOCKED:
+      // Shelf alignment changes can be requested while being locked, but will
+      // be applied upon unlock.
     case user::LOGGED_IN_USER:
     case user::LOGGED_IN_OWNER:
       return true;
-    case user::LOGGED_IN_LOCKED:
     case user::LOGGED_IN_PUBLIC:
     case user::LOGGED_IN_SUPERVISED:
     case user::LOGGED_IN_GUEST:
diff --git a/chrome/browser/ui/ash/launcher/launcher_context_menu.cc b/chrome/browser/ui/ash/launcher/launcher_context_menu.cc
index 2971b5d..22a4419 100644
--- a/chrome/browser/ui/ash/launcher/launcher_context_menu.cc
+++ b/chrome/browser/ui/ash/launcher/launcher_context_menu.cc
@@ -1,4 +1,4 @@
-// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Copyright 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.
 
@@ -9,6 +9,7 @@
 #include "ash/desktop_background/user_wallpaper_delegate.h"
 #include "ash/metrics/user_metrics_recorder.h"
 #include "ash/root_window_controller.h"
+#include "ash/session/session_state_delegate.h"
 #include "ash/shelf/shelf_item_delegate.h"
 #include "ash/shelf/shelf_widget.h"
 #include "ash/shell.h"
@@ -176,7 +177,8 @@ void LauncherContextMenu::Init() {
     AddCheckItemWithStringId(MENU_AUTO_HIDE,
                              IDS_ASH_SHELF_CONTEXT_MENU_AUTO_HIDE);
   }
-  if (ash::ShelfWidget::ShelfAlignmentAllowed()) {
+  if (ash::ShelfWidget::ShelfAlignmentAllowed() &&
+      !ash::Shell::GetInstance()->session_state_delegate()->IsScreenLocked()) {
     AddSubMenuWithStringId(MENU_ALIGNMENT_MENU,
                            IDS_ASH_SHELF_CONTEXT_MENU_POSITION,
                            &shelf_alignment_menu_);