Adding --disable-plugins-discovery command line switch to not load third-party plugins from common …

webkit/plugins/npapi/plugin_list.h

Index: webkit/plugins/npapi/plugin_list.h
===================================================================
--- webkit/plugins/npapi/plugin_list.h	(revision 204507)
+++ webkit/plugins/npapi/plugin_list.h	(working copy)
@@ -65,6 +65,10 @@
                            const std::string& mime_type,
                            bool allow_wildcard);
 
+  // Disables discovery of third_party plugins in standard places next time
+  // plugins are loaded.
+  void DisablePluginsDiscovery();
+
   // Cause the plugin list to refresh next time they are accessed, regardless
   // of whether they are already loaded.
   void RefreshPlugins();
@@ -284,6 +288,10 @@
   // accessed on multiple threads.
   base::Lock lock_;
 
+  // Flag indicating whether third_party plugins will be searched for
+  // in common places.
+  bool plugins_discovery_disabled_;
+
   DISALLOW_COPY_AND_ASSIGN(PluginList);
 };