Limit foreign fetch to only intercept requests made from secure contexts.

content/common/resource_request.h

Index: content/common/resource_request.h
diff --git a/content/common/resource_request.h b/content/common/resource_request.h
index dfd196f280ce4626819580d8206fc20b830e5f2e..6338c99a656761655cf57832448cae964c26f7d5 100644
--- a/content/common/resource_request.h
+++ b/content/common/resource_request.h
@@ -170,6 +170,9 @@ struct CONTENT_EXPORT ResourceRequest {
   // access to the body of the response that has already been fetched by the
   // browser.
   GURL resource_body_stream_url;
+
+  // Wether or not the initiator of this request is a secure context.
+  bool initiated_in_secure_context;
 };
 
 }  // namespace content