Stop creating shortcut for web apps when it is installing.

chrome/browser/ui/app_list/app_list_view_delegate.cc

Index: chrome/browser/ui/app_list/app_list_view_delegate.cc
diff --git a/chrome/browser/ui/app_list/app_list_view_delegate.cc b/chrome/browser/ui/app_list/app_list_view_delegate.cc
index 7b59b98f77fd6631d34ba5e7c347ada5dfb5f160..fc075babc02f6f5ef73ce1cbe95c862c4eb4a16f 100644
--- a/chrome/browser/ui/app_list/app_list_view_delegate.cc
+++ b/chrome/browser/ui/app_list/app_list_view_delegate.cc
@@ -102,7 +102,11 @@ void AppListViewDelegate::GetShortcutPathForApp(
   DCHECK(service);
   const extensions::Extension* extension =
       service->GetInstalledExtension(app_id);
-  DCHECK(extension);
+  if (!extension) {
+    // The installation of extension isn't finished yet.

[koz (OOO until 15th September), 2013/07/03 04:20:09]

This comment is unnecessary, could you remove it? (it's too specific - the
extension might not be there for any number of reasons).

[zhchbin, 2013/07/03 05:59:59]

Done.

+    callback.Run(base::FilePath());
+    return;
+  }
 
   base::FilePath app_data_dir(
       web_app::GetWebAppDataDirectory(profile_->GetPath(),