Add Accept-CH meta http-equiv support to the preloader.

Source/core/html/parser/HTMLPreloadScanner.cpp

 /*
  * Copyright (C) 2008 Apple Inc. All Rights Reserved.
  * Copyright (C) 2009 Torch Mobile, Inc. http://www.torchmobile.com/
  * Copyright (C) 2010 Google Inc. All Rights Reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
@@ skipping 148 matching lines @@
     }
 
     void handlePictureSourceURL(String& sourceURL)
     {
         if (match(m_tagImpl, sourceTag) && m_matchedMediaAttribute && sourceURL.isEmpty())
             sourceURL = m_srcsetImageCandidate.toString();
         else if (match(m_tagImpl, imgTag) && !sourceURL.isEmpty())
             setUrlToLoad(sourceURL, AllowURLReplacement);
     }
 
-    PassOwnPtr<PreloadRequest> createPreloadRequest(const KURL& predictedBaseURL, const SegmentedString& source)
+    PassOwnPtr<PreloadRequest> createPreloadRequest(const KURL& predictedBaseURL, const SegmentedString& source, const ClientHintsPreferences& clientHintsPreferences)
     {
         if (!shouldPreload() || !m_matchedMediaAttribute)
             return nullptr;
 
         TextPosition position = TextPosition(source.currentLine(), source.currentColumn());
         FetchRequest::ResourceWidth resourceWidth;
         if (m_sourceSizeSet && m_srcsetImageCandidate.resourceWidth() != UninitializedDescriptor) {
             resourceWidth.width = m_sourceSize;
             resourceWidth.isSet = true;
         }
-        OwnPtr<PreloadRequest> request = PreloadRequest::create(initiatorFor(m_tagImpl), position, m_urlToLoad, predictedBaseURL, resourceType(), resourceWidth);
+        OwnPtr<PreloadRequest> request = PreloadRequest::create(initiatorFor(m_tagImpl), position, m_urlToLoad, predictedBaseURL, resourceType(), resourceWidth, clientHintsPreferences);
         if (isCORSEnabled())
             request->setCrossOriginEnabled(allowStoredCredentials());
         request->setCharset(charset());
         request->setDefer(m_defer);
         return request.release();
     }
 
 private:
     template<typename NameType>
     void processScriptAttribute(const NameType& attributeName, const String& attributeValue)
@@ skipping 238 matching lines @@
 void TokenPreloadScanner::scan(const HTMLToken& token, const SegmentedString& source, PreloadRequestStream& requests)
 {
     scanCommon(token, source, requests);
 }
 
 void TokenPreloadScanner::scan(const CompactHTMLToken& token, const SegmentedString& source, PreloadRequestStream& requests)
 {
     scanCommon(token, source, requests);
 }
 
+static void handleMetaViewport(const String& attributeValue, CachedDocumentParameters* documentParameters)
+{
+    ViewportDescription description(ViewportDescription::ViewportMeta);
+    HTMLMetaElement::getViewportDescriptionFromContentAttribute(attributeValue, description, nullptr, documentParameters->viewportMetaZeroValuesQuirk);
+    FloatSize initialViewport(documentParameters->mediaValues->viewportHeight(), documentParameters->mediaValues->viewportWidth());
+    PageScaleConstraints constraints = description.resolve(initialViewport, documentParameters->defaultViewportMinWidth);
+    MediaValuesCached* cachedMediaValues = static_cast<MediaValuesCached*>(documentParameters->mediaValues.get());
+    cachedMediaValues->setViewportHeight(constraints.layoutSize.height());
+    cachedMediaValues->setViewportWidth(constraints.layoutSize.width());
+}
+
 template<typename Token>
 void TokenPreloadScanner::scanCommon(const Token& token, const SegmentedString& source, PreloadRequestStream& requests)
 {
     // Disable preload for documents with AppCache.
     if (m_isAppCacheEnabled)
         return;
 
     // http://crbug.com/434230 Disable preload for documents with CSP <meta> tags
     if (m_isCSPEnabled)
         return;
@@ skipping 40 matching lines @@
                 return;
             updatePredictedBaseURL(token);
             return;
         }
         if (match(tagImpl, htmlTag) && token.getAttributeItem(manifestAttr)) {
             m_isAppCacheEnabled = true;
             return;
         }
         if (match(tagImpl, metaTag)) {
             const typename Token::Attribute* equivAttribute = token.getAttributeItem(http_equivAttr);
-            if (equivAttribute && equalIgnoringCase(String(equivAttribute->value), "content-security-policy")) {
-                m_isCSPEnabled = true;
+            if (equivAttribute) {
+                String equivAttributeValue(equivAttribute->value);
+                if (equalIgnoringCase(equivAttributeValue, "content-security-policy"))
+                    m_isCSPEnabled = true;
+                else if (equalIgnoringCase(equivAttributeValue, "accept-ch"))
+                    handleAcceptClientHintsHeader(equivAttributeValue, m_clientHintsPreferences);
                 return;
             }
             const typename Token::Attribute* nameAttribute = token.getAttributeItem(nameAttr);
             if (nameAttribute && equalIgnoringCase(String(nameAttribute->value), "viewport")) {
                 const typename Token::Attribute* contentAttribute = token.getAttributeItem(contentAttr);
-
-                if (contentAttribute) {
-                    ViewportDescription description(ViewportDescription::ViewportMeta);
-                    HTMLMetaElement::getViewportDescriptionFromContentAttribute(String(contentAttribute->value), description, nullptr, m_documentParameters->viewportMetaZeroValuesQuirk);
-                    FloatSize initialViewport(m_documentParameters->mediaValues->viewportHeight(), m_documentParameters->mediaValues->viewportWidth());
-                    PageScaleConstraints constraints = description.resolve(initialViewport, m_documentParameters->defaultViewportMinWidth);
-                    MediaValuesCached* cachedMediaValues = static_cast<MediaValuesCached*>(m_documentParameters->mediaValues.get());
-                    cachedMediaValues->setViewportHeight(constraints.layoutSize.height());
-                    cachedMediaValues->setViewportWidth(constraints.layoutSize.width());
-                }
+                if (contentAttribute)
+                    handleMetaViewport(String(contentAttribute->value), m_documentParameters.get());
+                return;
             }
         }
 
         if (RuntimeEnabledFeatures::pictureEnabled() && (match(tagImpl, pictureTag))) {
             m_inPicture = true;
             m_pictureSourceURL = String();
             return;
         }
 
         StartTagScanner scanner(tagImpl, m_documentParameters->mediaValues);
         scanner.processAttributes(token.attributes());
         if (m_inPicture)
             scanner.handlePictureSourceURL(m_pictureSourceURL);
-        OwnPtr<PreloadRequest> request = scanner.createPreloadRequest(m_predictedBaseElementURL, source);
+        OwnPtr<PreloadRequest> request = scanner.createPreloadRequest(m_predictedBaseElementURL, source, m_clientHintsPreferences);
         if (request)
             requests.append(request.release());
         return;
     }
     default: {
         return;
     }
     }
 }
 
@@ skipping 51 matching lines @@
     if (givenMediaValues)
         mediaValues = givenMediaValues;
     else
         mediaValues = MediaValuesCached::create(*document);
     ASSERT(mediaValues->isSafeToSendToAnotherThread());
     defaultViewportMinWidth = document->viewportDefaultMinWidth();
     viewportMetaZeroValuesQuirk = document->settings() && document->settings()->viewportMetaZeroValuesQuirk();
 }
 
 }