Add fuzzer for HTMLPreloadScanner

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

Index: third_party/WebKit/Source/core/html/parser/HTMLPreloadScanner.h
diff --git a/third_party/WebKit/Source/core/html/parser/HTMLPreloadScanner.h b/third_party/WebKit/Source/core/html/parser/HTMLPreloadScanner.h
index 329795c691bc849b82ddb93bd3a6d6c097ca809a..628b2a0b83d70aadd9e53621be6f64998ef4172c 100644
--- a/third_party/WebKit/Source/core/html/parser/HTMLPreloadScanner.h
+++ b/third_party/WebKit/Source/core/html/parser/HTMLPreloadScanner.h
@@ -63,6 +63,11 @@ public:
         return wrapUnique(new CachedDocumentParameters(document));
     }
 
+    static std::unique_ptr<CachedDocumentParameters> create()
+    {
+        return wrapUnique(new CachedDocumentParameters);
+    }
+
     bool doHtmlPreloadScanning;
     bool doDocumentWritePreloadScanning;
     Length defaultViewportMinWidth;
@@ -72,6 +77,7 @@ public:
 
 private:
     explicit CachedDocumentParameters(Document*);
+    CachedDocumentParameters() = default;
 };
 
 class TokenPreloadScanner {