Don't create an empty text node when setting document.title to the empty string

Source/core/html/HTMLTitleElement.cpp

Index: Source/core/html/HTMLTitleElement.cpp
diff --git a/Source/core/html/HTMLTitleElement.cpp b/Source/core/html/HTMLTitleElement.cpp
index ff62d1c92a0824c76b4ba392ea626248a62fec5d..ed8a83c45a751814f561022de43b43aebfdb2a6e 100644
--- a/Source/core/html/HTMLTitleElement.cpp
+++ b/Source/core/html/HTMLTitleElement.cpp
@@ -89,11 +89,12 @@ void HTMLTitleElement::setText(const String &value)
     ChildListMutationScope mutation(*this);
 
     // Avoid calling Document::setTitleElement() during intermediate steps.
-    m_ignoreTitleUpdatesWhenChildrenChange = true;
+    m_ignoreTitleUpdatesWhenChildrenChange = !value.isEmpty();
     removeChildren();
     m_ignoreTitleUpdatesWhenChildrenChange = false;
 
-    appendChild(document().createTextNode(value.impl()), IGNORE_EXCEPTION);
+    if (!value.isEmpty())
+        appendChild(document().createTextNode(value.impl()), IGNORE_EXCEPTION);
 }
 
 }