Change CSSParserContext to have a Document handle (vs UseCounter).

third_party/WebKit/Source/core/css/parser/CSSLazyParsingState.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/parser/CSSLazyParsingState.h"
 #include "core/css/parser/CSSLazyPropertyParserImpl.h"
 #include "core/css/parser/CSSParserTokenRange.h"
 #include "core/dom/Document.h"
 #include "core/frame/UseCounter.h"
 #include "platform/Histogram.h"
@@ skipping 27 matching lines @@
   if (!m_shouldUseCount) {
     DCHECK(!m_context->isUseCounterRecordingEnabled());
     return m_context;
   }
 
   // Try as best as possible to grab a valid Document if the old Document has
   // gone away so we can still use UseCounter.
   if (!m_document)
     m_document = m_owningContents->anyOwnerDocument();
 
-  UseCounter* useCounter = UseCounter::getFrom(m_document);
-  if (useCounter != m_context->useCounter())
-    m_context = CSSParserContext::create(m_context, useCounter);
+  if (!m_context->isDocumentHandleEqual(m_document))
+    m_context = CSSParserContext::create(m_context, m_document);
   return m_context;
 }
 
 void CSSLazyParsingState::countRuleParsed() {
   ++m_parsedStyleRules;
   while (m_parsedStyleRules > m_styleRulesNeededForNextMilestone) {
     DCHECK_NE(UsageAll, m_usage);
     ++m_usage;
     recordUsageMetrics();
   }
@@ skipping 57 matching lines @@
   usageHistogram.count(m_usage);
 }
 
 DEFINE_TRACE(CSSLazyParsingState) {
   visitor->trace(m_owningContents);
   visitor->trace(m_document);
   visitor->trace(m_context);
 }
 
 }  // namespace blink