Prevent appearing INVALID position ordinal in sync.

chrome/browser/ui/app_list/chrome_app_list_item.cc

Index: chrome/browser/ui/app_list/chrome_app_list_item.cc
diff --git a/chrome/browser/ui/app_list/chrome_app_list_item.cc b/chrome/browser/ui/app_list/chrome_app_list_item.cc
index 934638ff7118a014ef787076e99404cc43c8c956..53a3cacfbe5b38830105ef27f9086d842c50e136 100644
--- a/chrome/browser/ui/app_list/chrome_app_list_item.cc
+++ b/chrome/browser/ui/app_list/chrome_app_list_item.cc
@@ -62,10 +62,18 @@ void ChromeAppListItem::UpdateFromSync(
 void ChromeAppListItem::SetDefaultPositionIfApplicable() {
   syncer::StringOrdinal page_ordinal;
   syncer::StringOrdinal launch_ordinal;
-  if (GetAppSorting()->GetDefaultOrdinals(id(), &page_ordinal,
-                                          &launch_ordinal) &&
-      page_ordinal.IsValid() && launch_ordinal.IsValid()) {
-    set_position(syncer::StringOrdinal(page_ordinal.ToInternalValue() +
-                                       launch_ordinal.ToInternalValue()));
+  extensions::AppSorting* app_sorting = GetAppSorting();

[khmel, 2017/01/04 20:22:52]

This does not guaranty generating position for all items.
https://cs.chromium.org/chromium/src/ui/app_list/app_list_item_list.cc?q=Ensu...
fixes such items however this is too late and before settings position there app
comes to sync service, when its position is still INVALID.

[stevenjb, 2017/01/04 20:34:26]

Aha. Good catch.

[khmel, 2017/01/04 21:15:12]

:( Kind of late. Also removed double set_position call.

+  if (!app_sorting->GetDefaultOrdinals(id(), &page_ordinal,
+                                       &launch_ordinal) ||
+      !page_ordinal.IsValid() || !launch_ordinal.IsValid()) {
+    app_sorting->EnsureValidOrdinals(id(), syncer::StringOrdinal());
+    page_ordinal = app_sorting->GetPageOrdinal(id());
+    launch_ordinal = app_sorting->GetAppLaunchOrdinal(id());
+    set_position(syncer::StringOrdinal(
+        page_ordinal.ToInternalValue() + launch_ordinal.ToInternalValue()));
   }
+  DCHECK(page_ordinal.IsValid());
+  DCHECK(launch_ordinal.IsValid());
+  set_position(syncer::StringOrdinal(page_ordinal.ToInternalValue() +
+                                     launch_ordinal.ToInternalValue()));
 }