Fix expected PlacementList sort order.

chrome/browser/chromeos/display/display_preferences.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 "chrome/browser/chromeos/display/display_preferences.h"
 
 #include <stddef.h>
 
 #include "ash/shell.h"
 #include "base/strings/string16.h"
@@ skipping 285 matching lines @@
   int rotation = display::Display::ROTATE_0;
   if (!properties->GetInteger("orientation", &rotation))
     return;
 
   GetDisplayManager()->RegisterDisplayRotationProperties(
       rotation_lock, static_cast<display::Display::Rotation>(rotation));
 }
 
 void StoreDisplayLayoutPref(const display::DisplayIdList& list,
                             const display::DisplayLayout& display_layout) {
+  DCHECK(display::DisplayLayout::Validate(list, display_layout));
   std::string name = display::DisplayIdListToString(list);
 
   PrefService* local_state = g_browser_process->local_state();
   DictionaryPrefUpdate update(local_state, prefs::kSecondaryDisplays);
   base::DictionaryValue* pref_data = update.Get();
   std::unique_ptr<base::Value> layout_value(new base::DictionaryValue());
   if (pref_data->HasKey(name)) {
     base::Value* value = nullptr;
     if (pref_data->Get(name, &value) && value != nullptr)
       layout_value.reset(value->DeepCopy());
   }
   if (display::DisplayLayoutToJson(display_layout, layout_value.get()))
     pref_data->Set(name, std::move(layout_value));
 }
 
 void StoreCurrentDisplayLayoutPrefs() {
   display::DisplayManager* display_manager = GetDisplayManager();
   if (!UserCanSaveDisplayPreference() ||
       display_manager->num_connected_displays() < 2) {
     return;
   }
 
   display::DisplayIdList list = display_manager->GetCurrentDisplayIdList();
   const display::DisplayLayout& display_layout =
       display_manager->layout_store()->GetRegisteredDisplayLayout(list);
+
+  if (!display::DisplayLayout::Validate(list, display_layout)) {
+    // We should never apply an invalid layout, if we do, it persists and the
+    // user has no way of fixing it except by deleting the local state.
+    LOG(ERROR) << "Attempting to store an invalid display layout in the local"
+               << " state. Skipping.";
+    return;
+  }
+
   StoreDisplayLayoutPref(list, display_layout);
 }
 
 void StoreCurrentDisplayProperties() {
   display::DisplayManager* display_manager = GetDisplayManager();
   PrefService* local_state = g_browser_process->local_state();
 
   DictionaryPrefUpdate update(local_state, prefs::kDisplayProperties);
   base::DictionaryValue* pref_data = update.Get();
 
@@ skipping 150 matching lines @@
   StoreDisplayPowerState(power_state);
 }
 
 bool ParseTouchCalibrationStringForTest(
     const std::string& str,
     display::TouchCalibrationData::CalibrationPointPairQuad* point_pair_quad) {
   return ParseTouchCalibrationStringValue(str, point_pair_quad);
 }
 
 }  // namespace chromeos