Pepper: Tighten GetLiveModule in PluginRegistry.

content/renderer/pepper/pepper_plugin_instance_impl.h

Index: content/renderer/pepper/pepper_plugin_instance_impl.h
diff --git a/content/renderer/pepper/pepper_plugin_instance_impl.h b/content/renderer/pepper/pepper_plugin_instance_impl.h
index cd419178e586bc6eb0c469fb8a33b7e519c80cc3..85d759cc765f85d0198cabd76d2405aead03876f 100644
--- a/content/renderer/pepper/pepper_plugin_instance_impl.h
+++ b/content/renderer/pepper/pepper_plugin_instance_impl.h
@@ -147,6 +147,9 @@ class CONTENT_EXPORT PepperPluginInstanceImpl
   // the WebPlugin implementation when WebKit is about to remove the plugin.
   void Delete();
 
+  // Returns true if Delete() has been called on this object.
+  bool is_deleted() const;
+
   // Paints the current backing store to the web page.
   void Paint(blink::WebCanvas* canvas,
              const gfx::Rect& plugin_rect,
@@ -848,6 +851,8 @@ class CONTENT_EXPORT PepperPluginInstanceImpl
 
   scoped_ptr<MouseLockDispatcher::LockTarget> lock_target_;
 
+  bool is_deleted_;
+
   // We use a weak ptr factory for scheduling DidChangeView events so that we
   // can tell whether updates are pending and consolidate them. When there's
   // already a weak ptr pending (HasWeakPtrs is true), code should update the