Make CSSParserContext be garbage collected.

third_party/WebKit/Source/core/css/resolver/SharedStyleFinderTest.cpp

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "core/css/resolver/SharedStyleFinder.h"
 
 #include "core/css/RuleFeature.h"
 #include "core/css/RuleSet.h"
 #include "core/css/parser/CSSParser.h"
 #include "core/css/parser/CSSParserContext.h"
@@ skipping 13 matching lines @@
 
   Document& document() { return m_dummyPageHolder->document(); }
 
   void setBodyContent(const String& html) {
     document().body()->setInnerHTML(html);
     document().view()->updateAllLifecyclePhases();
   }
 
   void addSelector(const String& selector) {
     StyleRuleBase* newRule =
-        CSSParser::parseRule(CSSParserContext(HTMLStandardMode, nullptr),
+        CSSParser::parseRule(CSSParserContext::create(HTMLStandardMode),
                              nullptr, selector + "{color:pink}");
     m_ruleSet->addStyleRule(static_cast<StyleRule*>(newRule),
                             RuleHasNoSpecialState);
   }
 
   void finishAddingSelectors() {
     m_siblingRuleSet = makeRuleSet(m_ruleSet->features().siblingRules());
     m_uncommonAttributeRuleSet =
         makeRuleSet(m_ruleSet->features().uncommonAttributeRules());
   }
@@ skipping 131 matching lines @@
   ASSERT_TRUE(b);
 
   EXPECT_FALSE(a->isDragged());
   EXPECT_FALSE(b->isDragged());
 
   EXPECT_TRUE(matchesUncommonAttributeRuleSet(*a));
   EXPECT_FALSE(matchesUncommonAttributeRuleSet(*b));
 }
 
 }  // namespace blink