Refactor PluginService to take PluginList as a dependency.

content/browser/plugin_service.cc

Index: content/browser/plugin_service.cc
diff --git a/content/browser/plugin_service.cc b/content/browser/plugin_service.cc
index 5e0e910656076fa2394cec4f57f871b1f52a079b..31df32e406dbae15563f6836f70a265c488909ff 100644
--- a/content/browser/plugin_service.cc
+++ b/content/browser/plugin_service.cc
@@ -76,6 +76,14 @@ void WillLoadPluginsCallback() {
 
 }  // namespace
 
+// Custom Singleton traits to inject the PluginList.
+struct PluginServiceSingletonTraits :
+    public DefaultSingletonTraits<PluginService> {
+  static PluginService* New() {
+    return new PluginService(webkit::npapi::PluginList::Singleton());

[Bernhard Bauer, 2011/11/08 17:03:23]

If you set the WillLoadPluginsCallback here, you don't need to reset it when
creating a TestPluginService.

[Robert Sesek, 2011/11/08 17:21:00]

Good idea. Done.

+  }
+};
+
 #if defined(OS_MACOSX)
 static void NotifyPluginsOfActivation() {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
@@ -109,11 +117,12 @@ class PluginDirWatcherDelegate : public FilePathWatcher::Delegate {
 
 // static
 PluginService* PluginService::GetInstance() {
-  return Singleton<PluginService>::get();
+  return Singleton<PluginService, PluginServiceSingletonTraits>::get();
 }
 
-PluginService::PluginService()
-    : ui_locale_(
+PluginService::PluginService(webkit::npapi::PluginList* a_plugin_list)
+    : plugin_list_(a_plugin_list),
+      ui_locale_(
           content::GetContentClient()->browser()->GetApplicationLocale()),
       filter_(NULL) {
   plugin_list()->set_will_load_plugins_callback(