Ignored title in shadow should cause StyleSheet.title = null.

third_party/WebKit/Source/core/html/HTMLLinkElement.cpp

Index: third_party/WebKit/Source/core/html/HTMLLinkElement.cpp
diff --git a/third_party/WebKit/Source/core/html/HTMLLinkElement.cpp b/third_party/WebKit/Source/core/html/HTMLLinkElement.cpp
index 5a9d71fb75063c7ea70baf978b181de4b6595559..211e788f07cf79774ca859f35eb98dac317a5083 100644
--- a/third_party/WebKit/Source/core/html/HTMLLinkElement.cpp
+++ b/third_party/WebKit/Source/core/html/HTMLLinkElement.cpp
@@ -472,7 +472,8 @@ void LinkStyle::setCSSStyleSheet(const String& href, const KURL& baseURL, const
             clearSheet();
         m_sheet = CSSStyleSheet::create(restoredSheet, m_owner);
         m_sheet->setMediaQueries(MediaQuerySet::create(m_owner->media()));
-        m_sheet->setTitle(m_owner->title());
+        if (m_owner->isInDocumentTree())
+            m_sheet->setTitle(m_owner->title());
         setCrossOriginStylesheetStatus(m_sheet.get());
 
         m_loading = false;
@@ -493,7 +494,8 @@ void LinkStyle::setCSSStyleSheet(const String& href, const KURL& baseURL, const
 
     m_sheet = CSSStyleSheet::create(styleSheet, m_owner);
     m_sheet->setMediaQueries(MediaQuerySet::create(m_owner->media()));
-    m_sheet->setTitle(m_owner->title());
+    if (m_owner->isInDocumentTree())
+        m_sheet->setTitle(m_owner->title());
     setCrossOriginStylesheetStatus(m_sheet.get());
 
     styleSheet->parseAuthorStyleSheet(cachedStyleSheet, m_owner->document().getSecurityOrigin());
@@ -709,7 +711,7 @@ void LinkStyle::process()
 
 void LinkStyle::setSheetTitle(const String& title)
 {
-    if (m_sheet)
+    if (m_sheet && m_owner->isInDocumentTree())
         m_sheet->setTitle(title);
 }