Emit error events if the loading of an object element failed

third_party/WebKit/public/web/WebPlugin.h

Index: third_party/WebKit/public/web/WebPlugin.h
diff --git a/third_party/WebKit/public/web/WebPlugin.h b/third_party/WebKit/public/web/WebPlugin.h
index 6e6403a7a6a5e5ce5129610d46044c0bbe83a7b6..f86e64af1d05cd684ca06e1126080003cc5eae84 100644
--- a/third_party/WebKit/public/web/WebPlugin.h
+++ b/third_party/WebKit/public/web/WebPlugin.h
@@ -236,8 +236,13 @@ class WebPlugin {
   virtual bool canRotateView() { return false; }
   // Rotates the plugin's view of its content.
   virtual void rotateView(RotationType type) {}
-
+  // Check whether a plugin can be interacted with. A positive return value
+  // means the plugin has not loaded and hence cannot be interacted with.
+  // The plugin could, however, load successfully later.
   virtual bool isPlaceholder() { return true; }
+  // Check whether a plugin failed to load, with there being no possibility of
+  // it loading later.
+  virtual bool isErrorPlaceholder() { return false; }
 
  protected:
   ~WebPlugin() {}