diff --git a/dom/base/nsDocument.h b/dom/base/nsDocument.h
index 27e4a6fd2094..a496680f8901 100644
--- a/dom/base/nsDocument.h
+++ b/dom/base/nsDocument.h
@@ -113,17 +113,6 @@ class nsDocument : public nsIDocument {
  protected:
   friend class nsNodeUtils;
 
-#define NS_DOCUMENT_NOTIFY_OBSERVERS(func_, params_)                          \
-  do {                                                                        \
-    NS_OBSERVER_ARRAY_NOTIFY_XPCOM_OBSERVERS(mObservers, nsIDocumentObserver, \
-                                             func_, params_);                 \
-    /* FIXME(emilio): Apparently we can keep observing from the BFCache? That \
-       looks bogus. */                                                        \
-    if (nsIPresShell* shell = GetObservingShell()) {                          \
-      shell->func_ params_;                                                   \
-    }                                                                         \
-  } while (0)
-
   explicit nsDocument(const char* aContentType);
   virtual ~nsDocument();
 
diff --git a/dom/base/nsIDocument.h b/dom/base/nsIDocument.h
index 34d5cc39bd1b..5863c9916f02 100644
--- a/dom/base/nsIDocument.h
+++ b/dom/base/nsIDocument.h
@@ -463,6 +463,17 @@ class nsIDocument : public nsINode,
 
   NS_DECL_ADDSIZEOFEXCLUDINGTHIS
 
+#define NS_DOCUMENT_NOTIFY_OBSERVERS(func_, params_)                          \
+  do {                                                                        \
+    NS_OBSERVER_ARRAY_NOTIFY_XPCOM_OBSERVERS(mObservers, nsIDocumentObserver, \
+                                             func_, params_);                 \
+    /* FIXME(emilio): Apparently we can keep observing from the BFCache? That \
+       looks bogus. */                                                        \
+    if (nsIPresShell* shell = GetObservingShell()) {                          \
+      shell->func_ params_;                                                   \
+    }                                                                         \
+  } while (0)
+
 #ifdef MOZILLA_INTERNAL_API
   nsIDocument();
 #endif