Pepper: Tighten GetLiveModule in PluginRegistry.

content/renderer/pepper/pepper_plugin_instance_impl.cc

Index: content/renderer/pepper/pepper_plugin_instance_impl.cc
diff --git a/content/renderer/pepper/pepper_plugin_instance_impl.cc b/content/renderer/pepper/pepper_plugin_instance_impl.cc
index af198b42521ae213c424eb40917736c7f4ce39d2..08e22dc790a401e8b3fa3775319ae2ac2c3861e3 100644
--- a/content/renderer/pepper/pepper_plugin_instance_impl.cc
+++ b/content/renderer/pepper/pepper_plugin_instance_impl.cc
@@ -524,6 +524,7 @@ PepperPluginInstanceImpl::PepperPluginInstanceImpl(
       external_document_load_(false),
       npp_(new NPP_t),
       isolate_(v8::Isolate::GetCurrent()),
+      is_deleted_(false),
       view_change_weak_ptr_factory_(this),
       weak_factory_(this) {
   pp_instance_ = HostGlobals::Get()->AddInstance(this);
@@ -601,6 +602,8 @@ PepperPluginInstanceImpl::~PepperPluginInstanceImpl() {
 // returned, then it needs to keep its own reference on the stack.
 
 void PepperPluginInstanceImpl::Delete() {
+  is_deleted_ = true;
+
   // Keep a reference on the stack. See NOTE above.
   scoped_refptr<PepperPluginInstanceImpl> ref(this);
   // Force the MessageChannel to release its "passthrough object" which should
@@ -631,6 +634,10 @@ void PepperPluginInstanceImpl::Delete() {
   container_ = NULL;
 }
 
+bool PepperPluginInstanceImpl::is_deleted() const {
+  return is_deleted_;
+}
+
 void PepperPluginInstanceImpl::Paint(WebCanvas* canvas,
                                      const gfx::Rect& plugin_rect,
                                      const gfx::Rect& paint_rect) {