Enabled CORS for chrome://resources.

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 33c185b63b87b5b8670f19f0590caad81eceefef..8650db3912d0a94407bd5b8248557b45fc9b9a09 100644
--- a/content/public/browser/url_data_source.h
+++ b/content/public/browser/url_data_source.h
@@ -119,6 +119,15 @@ class CONTENT_EXPORT URLDataSource {
   // is for chrome-devtools.
   virtual bool ShouldServeMimeTypeAsContentTypeHeader() const;
 
+  // This method is called when the request contains "Origin:" header. The value
+  // of the header is passed in |origin| parameter. If the returned value is not
+  // empty, it is used as a value for "Access-Control-Allow-Origin:" response
+  // header, otherwise the header is not set. This method should return either
+  // |origin|, or "*", or "none", or empty string.
+  // Default implementation returns an empty string.
+  virtual std::string GetAccessControlAllowOriginHeaderForOrigin(
+      const std::string& origin) const;
+
   // Called to inform the source that StartDataRequest() will be called soon.
   // Gives the source an opportunity to rewrite |path| to incorporate extra
   // information from the URLRequest prior to serving.