Add ReferrerPolicy support to preload

third_party/WebKit/Source/core/html/parser/HTMLPreloadScanner.cpp

Index: third_party/WebKit/Source/core/html/parser/HTMLPreloadScanner.cpp
diff --git a/third_party/WebKit/Source/core/html/parser/HTMLPreloadScanner.cpp b/third_party/WebKit/Source/core/html/parser/HTMLPreloadScanner.cpp
index b664912074081ba5a020b8c0980045d2d856b970..ba3c1cba895ed57d4d7f80c7997760dbf9ce781d 100644
--- a/third_party/WebKit/Source/core/html/parser/HTMLPreloadScanner.cpp
+++ b/third_party/WebKit/Source/core/html/parser/HTMLPreloadScanner.cpp
@@ -356,6 +356,12 @@ class TokenPreloadScanner::StartTagScanner {
     } else if (match(attributeName, typeAttr)) {
       m_matched &= MIMETypeRegistry::isSupportedStyleSheetMIMEType(
           ContentType(attributeValue).type());
+    } else if (!m_referrerPolicySet &&
+               match(attributeName, referrerpolicyAttr) &&
+               !attributeValue.isNull()) {
+      m_referrerPolicySet = true;
+      SecurityPolicy::referrerPolicyFromString(attributeValue,
+                                               &m_referrerPolicy);
     }
   }