Make setNeedsActiveStyleUpdate mark treescope dirty only.

third_party/WebKit/Source/core/dom/ProcessingInstruction.cpp

 /*
  * Copyright (C) 2000 Peter Kelly (pmk@post.com)
  * Copyright (C) 2006, 2008, 2009 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.
  *
  * This library is distributed in the hope that it will be useful,
@@ skipping 257 matching lines @@
   if (!insertionPoint->isConnected())
     return;
 
   // No need to remove XSLStyleSheet from StyleEngine.
   if (!DocumentXSLT::processingInstructionRemovedFromDocument(document(),
                                                               this)) {
     document().styleEngine().removeStyleSheetCandidateNode(*this,
                                                            *insertionPoint);
   }
 
-  StyleSheet* removedSheet = m_sheet;
   if (m_sheet) {
     DCHECK_EQ(m_sheet->ownerNode(), this);
     clearSheet();
   }
 
   // No need to remove pending sheets.
   clearResource();
 
+  // TODO(rune@opera.com): resolverChanged() can be removed once stylesheet
+  // updates are async. https://crbug.com/567021
   // If we're in document teardown, then we don't need to do any notification of
   // our sheet's removal.
   if (document().isActive())
-    document().styleEngine().setNeedsActiveStyleUpdate(removedSheet,
-                                                       FullStyleUpdate);
+    document().styleEngine().resolverChanged(FullStyleUpdate);
 }
 
 void ProcessingInstruction::clearSheet() {
   DCHECK(m_sheet);
   if (m_sheet->isLoading())
     document().styleEngine().removePendingSheet(*this, m_styleEngineContext);
   m_sheet.release()->clearOwnerNode();
 }
 
 DEFINE_TRACE(ProcessingInstruction) {
   visitor->trace(m_sheet);
   visitor->trace(m_listenerForXSLT);
   CharacterData::trace(visitor);
   ResourceOwner<StyleSheetResource>::trace(visitor);
 }
 
 }  // namespace blink