Have srcset respond to viewport changes

Source/core/html/parser/HTMLPreloadScanner.cpp

Index: Source/core/html/parser/HTMLPreloadScanner.cpp
diff --git a/Source/core/html/parser/HTMLPreloadScanner.cpp b/Source/core/html/parser/HTMLPreloadScanner.cpp
index 03d758daa34c9b747f93d7672e1446c740738227..5a2b627e901fcd6ad7fd2201778e11deab5343e3 100644
--- a/Source/core/html/parser/HTMLPreloadScanner.cpp
+++ b/Source/core/html/parser/HTMLPreloadScanner.cpp
@@ -116,8 +116,10 @@ public:
     {
         if (match(m_tagImpl, imgTag)
             || match(m_tagImpl, sourceTag)) {
-            if (RuntimeEnabledFeatures::pictureSizesEnabled())
-                m_sourceSize = SizesAttributeParser::findEffectiveSize(String(), m_mediaValues);
+            if (RuntimeEnabledFeatures::pictureSizesEnabled()) {
+                SizesAttributeParser parser = SizesAttributeParser(m_mediaValues, String());
+                m_sourceSize = parser.length();
+            }
             return;
         }
         if ( !match(m_tagImpl, inputTag)
@@ -197,7 +199,8 @@ private:
             m_srcsetImageCandidate = bestFitSourceForSrcsetAttribute(m_mediaValues->devicePixelRatio(), m_sourceSize, attributeValue);
             setUrlToLoad(bestFitSourceForImageAttributes(m_mediaValues->devicePixelRatio(), m_sourceSize, m_imgSrcUrl, m_srcsetImageCandidate), AllowURLReplacement);
         } else if (RuntimeEnabledFeatures::pictureSizesEnabled() && match(attributeName, sizesAttr) && !m_sourceSizeSet) {
-            m_sourceSize = SizesAttributeParser::findEffectiveSize(attributeValue, m_mediaValues);
+            SizesAttributeParser parser = SizesAttributeParser(m_mediaValues, attributeValue);
+            m_sourceSize = parser.length();
             m_sourceSizeSet = true;
             if (!m_srcsetImageCandidate.isEmpty()) {
                 m_srcsetImageCandidate = bestFitSourceForSrcsetAttribute(m_mediaValues->devicePixelRatio(), m_sourceSize, m_srcsetAttributeValue);
@@ -239,7 +242,8 @@ private:
             m_srcsetAttributeValue = attributeValue;
             m_srcsetImageCandidate = bestFitSourceForSrcsetAttribute(m_mediaValues->devicePixelRatio(), m_sourceSize, attributeValue);
         } else if (match(attributeName, sizesAttr) && !m_sourceSizeSet) {
-            m_sourceSize = SizesAttributeParser::findEffectiveSize(attributeValue, m_mediaValues);
+            SizesAttributeParser parser = SizesAttributeParser(m_mediaValues, attributeValue);
+            m_sourceSize = parser.length();
             m_sourceSizeSet = true;
             if (!m_srcsetImageCandidate.isEmpty()) {
                 m_srcsetImageCandidate = bestFitSourceForSrcsetAttribute(m_mediaValues->devicePixelRatio(), m_sourceSize, m_srcsetAttributeValue);