Fix expected PlacementList sort order.

chrome/browser/chromeos/display/display_preferences.cc

Index: chrome/browser/chromeos/display/display_preferences.cc
diff --git a/chrome/browser/chromeos/display/display_preferences.cc b/chrome/browser/chromeos/display/display_preferences.cc
index c6175250be6380c485d7671d25c612f86863555b..4beac908b985c2208c833d42d8c60d080f6c6f1c 100644
--- a/chrome/browser/chromeos/display/display_preferences.cc
+++ b/chrome/browser/chromeos/display/display_preferences.cc
@@ -328,6 +328,15 @@ void StoreCurrentDisplayLayoutPrefs() {
   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);
 }