DocumentLoader::isCommittedButEmpty is timing-dependent.

Source/core/loader/DocumentLoader.h

Index: Source/core/loader/DocumentLoader.h
diff --git a/Source/core/loader/DocumentLoader.h b/Source/core/loader/DocumentLoader.h
index 43fd4d53f10bdc57efa5caa7df651072ed759ee2..21f05683586aaec08f05860ce9a2c4f471b7be95 100644
--- a/Source/core/loader/DocumentLoader.h
+++ b/Source/core/loader/DocumentLoader.h
@@ -104,7 +104,7 @@ public:
     bool replacesCurrentHistoryItem() const { return m_replacesCurrentHistoryItem; }
     void setReplacesCurrentHistoryItem(bool replacesCurrentHistoryItem) { m_replacesCurrentHistoryItem = replacesCurrentHistoryItem; }
 
-    bool isCommittedButEmpty() const { return m_state == Committed; }
+    bool isCommittedButEmpty() const { return m_state == Committed || m_state == MainResourceDoneButEmpty; }
 
     bool shouldContinueForNavigationPolicy(const ResourceRequest&, ContentSecurityPolicyDisposition shouldCheckMainWorldContentSecurityPolicy, NavigationPolicy = NavigationPolicyCurrentTab);
     NavigationType navigationType() const { return m_navigationType; }
@@ -234,7 +234,8 @@ private:
         Provisional,
         Committed,
         DataReceived,
-        MainResourceDone
+        MainResourceDone,
+        MainResourceDoneButEmpty
     };
     State m_state;