Add HttpProtocolHandler and convert everything to use it

chromecast/browser/url_request_context_factory.cc

Index: chromecast/browser/url_request_context_factory.cc
diff --git a/chromecast/browser/url_request_context_factory.cc b/chromecast/browser/url_request_context_factory.cc
index 99013e0849096120e668ae237e9e8f94eb5f00a5..655df8bcade59e6d6058d9a64f32beffd0246bdb 100644
--- a/chromecast/browser/url_request_context_factory.cc
+++ b/chromecast/browser/url_request_context_factory.cc
@@ -227,8 +227,8 @@ void URLRequestContextFactory::InitializeMainContextDependencies(
     return;
 
   main_transaction_factory_.reset(transaction_factory);
-  std::unique_ptr<net::URLRequestJobFactoryImpl> job_factory(
-      new net::URLRequestJobFactoryImpl());
+  std::unique_ptr<net::URLRequestJobFactoryImpl> job_factory =
+      net::URLRequestJobFactoryImpl::CreateWithDefaultProtocolHandlers();
   // Keep ProtocolHandlers added in sync with
   // CastContentBrowserClient::IsHandledURL().
   bool set_protocol = false;
@@ -301,7 +301,8 @@ net::URLRequestContext* URLRequestContextFactory::CreateSystemRequestContext() {
   PopulateNetworkSessionParams(false, &system_params);
   system_transaction_factory_.reset(new net::HttpNetworkLayer(
       new net::HttpNetworkSession(system_params)));
-  system_job_factory_.reset(new net::URLRequestJobFactoryImpl());
+  system_job_factory_ =
+      net::URLRequestJobFactoryImpl::CreateWithDefaultProtocolHandlers();
   system_cookie_store_ =
       content::CreateCookieStore(content::CookieStoreConfig());