Propogate loading behavior data from Blink to content/

third_party/WebKit/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 533 matching lines @@
 
     if (equalIgnoringCase(nameAttributeValue, "referrer")) {
         handleMetaReferrer(contentAttributeValue, documentParameters, cssScanner);
     }
 }
 
 // This method returns true for script source strings which will likely use
 // document.write to insert an external script. These scripts will be flagged
 // for evaluation via the DocumentWriteEvaluator, so it also dismisses scripts
 // that will likely fail evaluation. These includes scripts that are too long,
-// have looping constructs, or use non-determinism.
+// have looping constructs, or use non-determinism. Note that flagging occurs
+// even when the experiment is off, to ensure fair comparison between experiment
+// and control groups.
 bool TokenPreloadScanner::shouldEvaluateForDocumentWrite(const String& source)
 {
     // The maximum length script source that will be marked for evaluation to
     // preload document.written external scripts.
     const int kMaxLengthForEvaluating = 1024;
 
     return m_documentParameters->doDocumentWritePreloadScanning
         && source.length() <= kMaxLengthForEvaluating
         && source.find("document.write") != WTF::kNotFound
         && (source.findIgnoringASCIICase("<sc") != WTF::kNotFound
@@ skipping 166 matching lines @@
     }
 
     preloader->takeAndPreload(requests);
 }
 
 CachedDocumentParameters::CachedDocumentParameters(Document* document)
 {
     ASSERT(isMainThread());
     ASSERT(document);
     doHtmlPreloadScanning = !document->settings() || document->settings()->doHtmlPreloadScanning();
-    doDocumentWritePreloadScanning = doHtmlPreloadScanning && document->frame() && document->frame()->isMainFrame() && RuntimeEnabledFeatures::documentWriteEvaluatorEnabled();
+    doDocumentWritePreloadScanning = doHtmlPreloadScanning && document->frame() && document->frame()->isMainFrame();
     defaultViewportMinWidth = document->viewportDefaultMinWidth();
     viewportMetaZeroValuesQuirk = document->settings() && document->settings()->viewportMetaZeroValuesQuirk();
     viewportMetaEnabled = document->settings() && document->settings()->viewportMetaEnabled();
     referrerPolicy = ReferrerPolicyDefault;
 }
 
 } // namespace blink