Support Service Worker NavigationPreload with PlzNavigate.

content/browser/renderer_host/render_process_host_impl.cc

Index: content/browser/renderer_host/render_process_host_impl.cc
diff --git a/content/browser/renderer_host/render_process_host_impl.cc b/content/browser/renderer_host/render_process_host_impl.cc
index f1dcab31fb7bf1deff1b29dae91138238d9d70b0..38f2c380cc380a89a39f036559246aefcc799cc4 100644
--- a/content/browser/renderer_host/render_process_host_impl.cc
+++ b/content/browser/renderer_host/render_process_host_impl.cc
@@ -1140,8 +1140,7 @@ void RenderProcessHostImpl::CreateMessageFilters() {
   scoped_refptr<ServiceWorkerDispatcherHost> service_worker_filter =
       new ServiceWorkerDispatcherHost(
           GetID(), message_port_message_filter_.get(), resource_context,
-          base::Bind(&RenderProcessHostImpl::CreateURLLoaderFactory,
-                     weak_factory_.GetWeakPtr()));
+          CreateURLLoaderFactoryGetter());
   service_worker_filter->Init(
       storage_partition_impl_->GetServiceWorkerContext());
   AddFilter(service_worker_filter.get());
@@ -1409,6 +1408,12 @@ mojom::Renderer* RenderProcessHostImpl::GetRendererInterface() {
   return renderer_interface_.get();
 }
 
+MojoURLLoaderFactoryGetter
+RenderProcessHostImpl::CreateURLLoaderFactoryGetter() {
+  return base::Bind(&RenderProcessHostImpl::CreateURLLoaderFactory,
+                    weak_factory_.GetWeakPtr());

[horo, 2016/10/31 14:50:32]

WeakPtr is not thread safe.
So we should not pass the MojoURLLoaderFactoryGetter to the IO thread.
http://www.chromium.org/developers/design-documents/threading#base_WeakPtr_an...

I will create another CL to avoid this problem.

Sorry for confusion.

[piman, 2016/10/31 20:43:25]

I'll wait for the update before a full review. Just one thing: if there are
specific expectations about the value returned from CreateURLLoaderFactoryGetter
(i.e. used on a different thread than where it's queried?), can you document
that in the API?

FYI, WeakPtr is not generally thread-safe, however it can be copied to other
threads - I don't know if that matters to you. The restriction is that it can
only be dereferenced  on the same thread as it gets cancelled (i.e. the thread
the WeakPtrFactory gets destroyed).

+}
+
 mojom::RouteProvider* RenderProcessHostImpl::GetRemoteRouteProvider() {
   return remote_route_provider_.get();
 }