Add an extra guard to replaceDocument()

Source/core/dom/DocumentInit.cpp

Index: Source/core/dom/DocumentInit.cpp
diff --git a/Source/core/dom/DocumentInit.cpp b/Source/core/dom/DocumentInit.cpp
index aeff8ba7b42836478af1c0cbab47a558fecef830..31b8feb749b00dbf32219092a59d316a4d7ace3f 100644
--- a/Source/core/dom/DocumentInit.cpp
+++ b/Source/core/dom/DocumentInit.cpp
@@ -70,6 +70,7 @@ DocumentInit::DocumentInit(const KURL& url, LocalFrame* frame, WeakPtrWillBeRawP
     , m_contextDocument(contextDocument)
     , m_importsController(importsController)
     , m_createNewRegistrationContext(false)
+    , m_shouldReuseDefaultView(frame && frame->shouldReuseDefaultView(url))
 {
 }
 
@@ -82,6 +83,7 @@ DocumentInit::DocumentInit(const DocumentInit& other)
     , m_importsController(other.m_importsController)
     , m_registrationContext(other.m_registrationContext)
     , m_createNewRegistrationContext(other.m_createNewRegistrationContext)
+    , m_shouldReuseDefaultView(other.m_shouldReuseDefaultView)
 {
 }