Headless: Remove obsolete Mojo code and some other obsolete APIs

headless/public/util/deterministic_http_protocol_handler.cc

Index: headless/public/util/deterministic_http_protocol_handler.cc
diff --git a/headless/public/util/deterministic_http_protocol_handler.cc b/headless/public/util/deterministic_http_protocol_handler.cc
index 1f61f9827d2c43dcd0a5475a084661e248844118..1c9521e4281c5188450c42f58cc7c86c33f34c38 100644
--- a/headless/public/util/deterministic_http_protocol_handler.cc
+++ b/headless/public/util/deterministic_http_protocol_handler.cc
@@ -44,6 +44,7 @@ DeterministicHttpProtocolHandler::DeterministicHttpProtocolHandler(
     DeterministicDispatcher* deterministic_dispatcher,
     scoped_refptr<base::SingleThreadTaskRunner> io_task_runner)
     : deterministic_dispatcher_(deterministic_dispatcher),
+      headless_browser_context_(nullptr),
       io_task_runner_(io_task_runner),
       nop_delegate_(new NopGenericURLRequestJobDelegate()) {}
 
@@ -69,7 +70,7 @@ net::URLRequestJob* DeterministicHttpProtocolHandler::MaybeCreateJob(
   return new GenericURLRequestJob(
       request, network_delegate, deterministic_dispatcher_,
       base::MakeUnique<HttpURLFetcher>(url_request_context_.get()),
-      nop_delegate_.get());
+      nop_delegate_.get(), headless_browser_context_);
 }
 
 }  // namespace headless