Always install a BookmarkUndoService as a BookmarkModelObserver on iOS

chrome/browser/bookmarks/bookmark_model_factory.cc

Index: chrome/browser/bookmarks/bookmark_model_factory.cc
diff --git a/chrome/browser/bookmarks/bookmark_model_factory.cc b/chrome/browser/bookmarks/bookmark_model_factory.cc
index 92e0e35cea818abc462ed40bc5e8d499d8ac6a1b..21c2d46a3b91deaf1262ac78b6709586dcf8d13f 100644
--- a/chrome/browser/bookmarks/bookmark_model_factory.cc
+++ b/chrome/browser/bookmarks/bookmark_model_factory.cc
@@ -65,8 +65,14 @@ KeyedService* BookmarkModelFactory::BuildServiceInstanceFor(
       content::BrowserThread::GetMessageLoopProxyForThread(
           content::BrowserThread::UI));
 #if !defined(OS_ANDROID)
-  if (CommandLine::ForCurrentProcess()->HasSwitch(
-     switches::kEnableBookmarkUndo)) {
+#if !defined(OS_IOS)
+  bool register_bookmark_undo_service_as_observer =
+      CommandLine::ForCurrentProcess()->HasSwitch(
+          switches::kEnableBookmarkUndo);
+#else
+  bool register_bookmark_undo_service_as_observer = true;

[blundell, 2014/05/05 13:08:15]

I think this would be less confusing with this line hoisted up to be underneath
line 67 and no else clause in the "if !defined(OS_IOS)" block.

[sdefresne, 2014/05/05 14:37:11]

Done.

+#endif  // !defined(OS_IOS)
+  if (register_bookmark_undo_service_as_observer) {
     bookmark_client->model()->AddObserver(
         BookmarkUndoServiceFactory::GetForProfile(profile));
   }