Filter out data urls in the preload scanner

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

Index: third_party/WebKit/Source/core/html/parser/HTMLResourcePreloader.cpp
diff --git a/third_party/WebKit/Source/core/html/parser/HTMLResourcePreloader.cpp b/third_party/WebKit/Source/core/html/parser/HTMLResourcePreloader.cpp
index 0e1bd5f6a963dd8b512c77afe9a448899c73f8f8..1eb352eee68676dae629eb26b0f80330984aba21 100644
--- a/third_party/WebKit/Source/core/html/parser/HTMLResourcePreloader.cpp
+++ b/third_party/WebKit/Source/core/html/parser/HTMLResourcePreloader.cpp
@@ -77,11 +77,10 @@ void HTMLResourcePreloader::preload(
   if (!m_document->loader())
     return;
   FetchRequest request = preload->resourceRequest(m_document);
-  // TODO(dgozman): This check should go to HTMLPreloadScanner, but this
-  // requires making Document::completeURLWithOverride logic to be statically
-  // accessible.
-  if (request.url().protocolIsData())
-    return;
+
+  // Data URLs are filtered out in the preload scanner.
+  DCHECK(!request.url().protocolIsData());
+
   if (preload->resourceType() == Resource::Script ||
       preload->resourceType() == Resource::CSSStyleSheet ||
       preload->resourceType() == Resource::ImportResource)