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..b0cbb7f8541d197993ecd71711b38af3b7b4d640 100644
--- a/content/browser/plugin_service.cc
+++ b/content/browser/plugin_service.cc
@@ -113,9 +113,30 @@ PluginService* PluginService::GetInstance() {
 }
 
 PluginService::PluginService()
-    : ui_locale_(
+    : plugin_list_(NULL),
+      ui_locale_(
           content::GetContentClient()->browser()->GetApplicationLocale()),
       filter_(NULL) {
+}
+
+PluginService::~PluginService() {
+#if defined(OS_WIN)
+  // Release the events since they're owned by RegKey, not WaitableEvent.
+  hkcu_watcher_.StopWatching();
+  hklm_watcher_.StopWatching();
+  if (hkcu_event_.get())
+    hkcu_event_->Release();
+  if (hklm_event_.get())
+    hklm_event_->Release();
+#endif
+  // Make sure no plugin channel requests have been leaked.
+  DCHECK(pending_plugin_clients_.empty());
+}
+
+void PluginService::Init() {
+  if (!plugin_list_)
+    plugin_list_ = webkit::npapi::PluginList::Singleton();
+
   plugin_list()->set_will_load_plugins_callback(
       base::Bind(&WillLoadPluginsCallback));
 
@@ -140,20 +161,6 @@ PluginService::PluginService()
 #endif
 }
 
-PluginService::~PluginService() {
-#if defined(OS_WIN)
-  // Release the events since they're owned by RegKey, not WaitableEvent.
-  hkcu_watcher_.StopWatching();
-  hklm_watcher_.StopWatching();
-  if (hkcu_event_.get())
-    hkcu_event_->Release();
-  if (hklm_event_.get())
-    hklm_event_->Release();
-#endif
-  // Make sure no plugin channel requests have been leaked.
-  DCHECK(pending_plugin_clients_.empty());
-}
-
 void PluginService::StartWatchingPlugins() {
   // Start watching for changes in the plugin list. This means watching
   // for changes in the Windows registry keys and on both Windows and POSIX
@@ -640,6 +647,11 @@ webkit::npapi::PluginList* PluginService::plugin_list() {
   return webkit::npapi::PluginList::Singleton();
 }
 
+void PluginService::SetPluginListForTesting(
+    webkit::npapi::PluginList* plugin_list) {
+  plugin_list_ = plugin_list;
+}
+
 void PluginService::RegisterInternalPlugin(const webkit::WebPluginInfo& info) {
   plugin_list()->RegisterInternalPlugin(info);
 }