Fix overlapping of shelf options on supervised user creation page when rotating screen

chrome/browser/ui/ash/launcher/chrome_launcher_controller_impl.cc

 // Copyright 2013 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 "chrome/browser/ui/ash/launcher/chrome_launcher_controller_impl.h"
 
 #include <stddef.h>
 
 #include <vector>
 
@@ skipping 1651 matching lines @@
 }
 
 void ChromeLauncherControllerImpl::ShelfItemChanged(
     int index,
     const ash::ShelfItem& old_item) {}
 
 ///////////////////////////////////////////////////////////////////////////////
 // ash::WindowTreeHostManager::Observer:
 
 void ChromeLauncherControllerImpl::OnDisplayConfigurationChanged() {
+  // In BOTTOM_LOCKED state, ignore the call of SetShelfBehaviorsFromPrefs.
+  // Because it might be called by some operations, like crbug.com/627040
+  // rotating screen.
+  ash::Shelf* shelf = ash::Shelf::ForPrimaryDisplay();
+  if (shelf && shelf->alignment() == ash::SHELF_ALIGNMENT_BOTTOM_LOCKED)
+    return;

[stevenjb, 2016/07/11 22:04:24]

nit: Normally we prefer early exit like this, however in this case since this is
a Changed() handler it might be better to invert the if and move
SetShelfBehaviorsFromPrefs() to the if body, that way if additional code gets
added to this handler it will still get called. (That said, anybody adding code
should notice and make the change, so this is also fine as-is).

[Qiang(Joe) Xu, 2016/07/11 22:27:52]

done. tks for this tip.

   SetShelfBehaviorsFromPrefs();
 }
 
 ///////////////////////////////////////////////////////////////////////////////
 // AppSyncUIStateObserver:
 
 void ChromeLauncherControllerImpl::OnAppSyncUIStatusChanged() {
   if (app_sync_ui_state_->status() == AppSyncUIState::STATUS_SYNCING)
     model_->set_status(ash::ShelfModel::STATUS_LOADING);
   else
@@ skipping 19 matching lines @@
     if (index == -1)
       continue;
     ash::ShelfItem item = model_->items()[index];
     item.image = image;
     if (arc_deferred_launcher_)
       arc_deferred_launcher_->MaybeApplySpinningEffect(id, &item.image);
     model_->Set(index, item);
     // It's possible we're waiting on more than one item, so don't break.
   }
 }