Current work-in-progress crbug.com/567021

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 187 matching lines @@
     }
 
     DCHECK(m_isCSS);
     CSSParserContext parserContext(document(), 0, baseURL, charset);
 
     StyleSheetContents* newSheet = StyleSheetContents::create(href, parserContext);
 
     CSSStyleSheet* cssSheet = CSSStyleSheet::create(newSheet, this);
     cssSheet->setDisabled(m_alternate);
     cssSheet->setTitle(m_title);
+    if (!m_alternate && !m_title.isEmpty())
+        document().styleEngine().setPreferredStylesheetSetNameIfNotSet(m_title);
     cssSheet->setMediaQueries(MediaQuerySet::create(m_media));
 
     m_sheet = cssSheet;
 
     // We don't need the cross-origin security check here because we are
     // getting the sheet text in "strict" mode. This enforces a valid CSS MIME
     // type.
     parseStyleSheet(sheet->sheetText());
 }
 
@@ skipping 45 matching lines @@
 void ProcessingInstruction::removedFrom(ContainerNode* insertionPoint)
 {
     CharacterData::removedFrom(insertionPoint);
     if (!insertionPoint->inShadowIncludingDocument())
         return;
 
     // No need to remove XSLStyleSheet from StyleEngine.
     if (!DocumentXSLT::processingInstructionRemovedFromDocument(document(), this))
         document().styleEngine().removeStyleSheetCandidateNode(this);
 
-    StyleSheet* removedSheet = m_sheet;
     if (m_sheet) {
         DCHECK_EQ(m_sheet->ownerNode(), this);
         clearSheet();
+        document().styleEngine().setNeedsActiveStyleUpdate(treeScope());
     }
 
     // No need to remove pending sheets.
     clearResource();
-
-    // 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);
 }
 
 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