Make CSSParserContext be garbage collected.

third_party/WebKit/Source/core/html/LinkStyle.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/html/LinkStyle.h"
 
 #include "core/css/StyleSheetContents.h"
 #include "core/frame/LocalFrame.h"
 #include "core/frame/SubresourceIntegrity.h"
 #include "core/frame/csp/ContentSecurityPolicy.h"
@@ skipping 89 matching lines @@
 
     if (disposition == ResourceIntegrityDisposition::Failed) {
       m_loading = false;
       removePendingSheet();
       notifyLoadedSheetAndAllCriticalSubresources(
           Node::ErrorOccurredLoadingSubresource);
       return;
     }
   }
 
-  CSSParserContext parserContext(m_owner->document(), nullptr, baseURL,
-                                 charset);
+  CSSParserContext* parserContext =
+      CSSParserContext::create(m_owner->document(), baseURL, charset);
 
   DEFINE_STATIC_LOCAL(EnumerationHistogram, restoredCachedStyleSheetHistogram,
                       ("Blink.RestoredCachedStyleSheet", 2));
   DEFINE_STATIC_LOCAL(
       EnumerationHistogram, restoredCachedStyleSheet2Histogram,
       ("Blink.RestoredCachedStyleSheet2", StyleSheetCacheStatusCount));
 
   if (StyleSheetContents* restoredSheet =
           const_cast<CSSStyleSheetResource*>(cachedStyleSheet)
               ->restoreParsedStyleSheet(parserContext)) {
@@ skipping 293 matching lines @@
     removePendingSheet();
 }
 
 DEFINE_TRACE(LinkStyle) {
   visitor->trace(m_sheet);
   LinkResource::trace(visitor);
   ResourceOwner<StyleSheetResource>::trace(visitor);
 }
 
 }  // namespace blink