feat: migrate protocol module to NetworkService (Part 5) (#18170)

* fix: always have head.headers available

* fix: use StringDataPipeProducer to write string

It can handle large strings correctly.

* fix: override RegisterNonNetworkSubresourceURLLoaderFactories

* fix: add dummy uninterceptProtocol implementation

* fix: jquery error handler can pass empty string

For some errors jquery would pass empty string in the error handler,
which makes tests pass when they should fail.

* chore: fix cpplint warnings

* fix: guard RegisterNonNetworkSubresourceURLLoaderFactories call

It may be called even when NetworkService is not enabled.

* test: disable protocol.interceptHttpProtocol test

atom/browser/net/atom_url_loader_factory.h

@@ -86,8 +86,7 @@ class AtomURLLoaderFactory : public network::mojom::URLLoaderFactory {
   // Helper to send string as response.
   static void SendContents(network::mojom::URLLoaderClientPtr client,
                            network::ResourceResponseHead head,
-                           const char* data,
-                           size_t size);
+                           std::string data);
 
   // TODO(zcbenz): This comes from extensions/browser/extension_protocols.cc
   // but I don't know what it actually does, find out the meanings of |Clone|