1 files changed, 10 insertions, 0 deletions
diff --git a/dom/base/DocGroup.h b/dom/base/DocGroup.h
index f4f7ac8ad..5b8f627cc 100644
--- a/dom/base/DocGroup.h
+++ b/dom/base/DocGroup.h
@@ -14,6 +14,7 @@
 #include "nsString.h"
 
 #include "mozilla/RefPtr.h"
+#include "mozilla/dom/CustomElementRegistry.h"
 
 namespace mozilla {
 namespace dom {
@@ -52,6 +53,14 @@ public:
   {
     return mTabGroup;
   }
+  mozilla::dom::CustomElementReactionsStack* CustomElementReactionsStack()
+  {
+    if (!mReactionsStack) {
+      mReactionsStack = new mozilla::dom::CustomElementReactionsStack();
+    }
+
+    return mReactionsStack;
+  }
   void RemoveDocument(nsIDocument* aWindow);
 
   // Iterators for iterating over every document within the DocGroup
@@ -71,6 +80,7 @@ private:
   nsCString mKey;
   RefPtr<TabGroup> mTabGroup;
   nsTArray<nsIDocument*> mDocuments;
+  RefPtr<mozilla::dom::CustomElementReactionsStack> mReactionsStack;
 };
 
 } // namespace dom