DO NOT COMMIT: hack hack hacking on preloading md-settings

content/public/browser/url_data_source.h

Index: content/public/browser/url_data_source.h
diff --git a/content/public/browser/url_data_source.h b/content/public/browser/url_data_source.h
index 111cc20cb11b3061b6b4149ef629db76770dd08f..097303d9776aa1057a6bf555fe07344e8cc72882 100644
--- a/content/public/browser/url_data_source.h
+++ b/content/public/browser/url_data_source.h
@@ -6,6 +6,7 @@
 #define CONTENT_PUBLIC_BROWSER_URL_DATA_SOURCE_H_
 
 #include <string>
+#include <vector>
 
 #include "base/callback.h"
 #include "base/memory/ref_counted.h"
@@ -118,6 +119,8 @@ class CONTENT_EXPORT URLDataSource {
   // happening, return false. It is OK to return false as needed.
   virtual bool ShouldDenyXFrameOptions() const;
 
+  virtual std::vector<std::string> GetPreloadHeaders() const;
+
   // By default, only chrome: and chrome-devtools: requests are allowed.
   // Override in specific WebUI data sources to enable for additional schemes or
   // to implement fancier access control.  Typically used in concert with