Add URLRequestJobFactories to URLRequestContexts without one.

sync/internal_api/http_bridge.cc

Index: sync/internal_api/http_bridge.cc
diff --git a/sync/internal_api/http_bridge.cc b/sync/internal_api/http_bridge.cc
index ffcaf9a9c2e5cc728322c1b83306df60a9693fd4..c4e096ca09e4d2ed55ae2c6b090809a44297e73a 100644
--- a/sync/internal_api/http_bridge.cc
+++ b/sync/internal_api/http_bridge.cc
@@ -16,6 +16,7 @@
 #include "net/url_request/static_http_user_agent_settings.h"
 #include "net/url_request/url_fetcher.h"
 #include "net/url_request/url_request_context.h"
+#include "net/url_request/url_request_job_factory_impl.h"
 #include "net/url_request/url_request_status.h"
 #include "sync/internal_api/public/base/cancelation_signal.h"
 
@@ -122,7 +123,8 @@ HttpBridge::RequestContext::RequestContext(
         network_task_runner,
     const std::string& user_agent)
     : baseline_context_(baseline_context),
-      network_task_runner_(network_task_runner) {
+      network_task_runner_(network_task_runner),
+      job_factory_(new net::URLRequestJobFactoryImpl()) {
   DCHECK(!user_agent.empty());
 
   // Create empty, in-memory cookie store.
@@ -133,6 +135,9 @@ HttpBridge::RequestContext::RequestContext(
   set_proxy_service(baseline_context->proxy_service());
   set_ssl_config_service(baseline_context->ssl_config_service());
 
+  // Use its own job factory, which only supports http and https.
+  set_job_factory(job_factory_.get());
+
   // We want to share the HTTP session data with the network layer factory,
   // which includes auth_cache for proxies.
   // Session is not refcounted so we need to be careful to not lose the parent