Index: third_party/WebKit/Source/core/dom/DocumentVisibilityObserver.h |
diff --git a/third_party/WebKit/Source/core/dom/DocumentVisibilityObserver.h b/third_party/WebKit/Source/core/dom/DocumentVisibilityObserver.h |
index 967de8b2767baa7d291d1f087da699bfd7d7ddc4..188db53e96bf927d5f22f87d17845c9f8c6a4834 100644 |
--- a/third_party/WebKit/Source/core/dom/DocumentVisibilityObserver.h |
+++ b/third_party/WebKit/Source/core/dom/DocumentVisibilityObserver.h |
@@ -20,6 +20,7 @@ public: |
virtual ~DocumentVisibilityObserver(); |
virtual void didChangeVisibilityState(PageVisibilityState) = 0; |
+ virtual void willDetachDocument() = 0; |
// Classes that inherit Node and DocumentVisibilityObserver must have a |
// virtual override of Node::didMoveToNewDocument that calls |