PageRule should not serialize @page in selectorText

third_party/WebKit/Source/core/css/CSSPageRule.cpp

 /*
  * (C) 1999-2003 Lars Knoll (knoll@kde.org)
  * (C) 2002-2003 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2002, 2005, 2006, 2008, 2012 Apple Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
@@ skipping 37 matching lines @@
 CSSStyleDeclaration* CSSPageRule::style() const
 {
     if (!m_propertiesCSSOMWrapper)
         m_propertiesCSSOMWrapper = StyleRuleCSSStyleDeclaration::create(m_pageRule->mutableProperties(), const_cast<CSSPageRule*>(this));
     return m_propertiesCSSOMWrapper.get();
 }
 
 String CSSPageRule::selectorText() const
 {
     StringBuilder text;
-    text.appendLiteral("@page");
     const CSSSelector* selector = m_pageRule->selector();
     if (selector) {
         String pageSpecification = selector->selectorText();
-        if (!pageSpecification.isEmpty() && pageSpecification != starAtom) {
-            text.append(' ');
+        if (!pageSpecification.isEmpty())
             text.append(pageSpecification);
-        }
     }
     return text.toString();
 }
 
 void CSSPageRule::setSelectorText(const String& selectorText)
 {
     CSSParserContext context(parserContext(), 0);
     CSSSelectorList selectorList = CSSParser::parseSelector(context, parentStyleSheet() ? parentStyleSheet()->contents() : nullptr, selectorText);
     if (!selectorList.isValid())
         return;
 
     CSSStyleSheet::RuleMutationScope mutationScope(this);
 
     m_pageRule->wrapperAdoptSelectorList(std::move(selectorList));
 }
 
 String CSSPageRule::cssText() const
 {
     StringBuilder result;
-    result.append(selectorText());
-    result.appendLiteral(" { ");
+    result.appendLiteral("@page ");
+    String pageSelectors = selectorText();
+    result.append(pageSelectors);
+    if (!pageSelectors.isEmpty())
+        result.appendLiteral(" ");
+    result.appendLiteral("{ ");
     String decls = m_pageRule->properties().asText();
     result.append(decls);
     if (!decls.isEmpty())
         result.append(' ');
     result.append('}');
     return result.toString();
 }
 
 void CSSPageRule::reattach(StyleRuleBase* rule)
 {
     ASSERT(rule);
     m_pageRule = toStyleRulePage(rule);
     if (m_propertiesCSSOMWrapper)
         m_propertiesCSSOMWrapper->reattach(m_pageRule->mutableProperties());
 }
 
 DEFINE_TRACE(CSSPageRule)
 {
     visitor->trace(m_pageRule);
     visitor->trace(m_propertiesCSSOMWrapper);
     CSSRule::trace(visitor);
 }
 
 } // namespace blink