Restart plugin loading only if the plugin list has actually become stale.

content/browser/plugin_service_impl.h

Index: content/browser/plugin_service_impl.h
diff --git a/content/browser/plugin_service_impl.h b/content/browser/plugin_service_impl.h
index e95fa7c9786455125945a1a398ecdd606cf96d06..92976287f3a046140f2e52f721835b0dbe4a2279 100644
--- a/content/browser/plugin_service_impl.h
+++ b/content/browser/plugin_service_impl.h
@@ -185,6 +185,12 @@ class CONTENT_EXPORT PluginServiceImpl
   void GetPluginsInternal(base::MessageLoopProxy* target_loop,
                           const GetPluginsCallback& callback);
 
+#if defined(OS_POSIX)
+  void GetPluginsOnIOThread(
+      base::MessageLoopProxy* target_loop,
+      const GetPluginsCallback& callback);
+#endif
+
   // Binding directly to GetAllowedPluginForOpenChannelToPlugin() isn't possible
   // because more arity is needed <http://crbug.com/98542>. This just forwards.
   void ForwardGetAllowedPluginForOpenChannelToPlugin(