network service: pass PlzNavigate resulting data via mojo data pipe

content/child/web_url_loader_impl.cc

Index: content/child/web_url_loader_impl.cc
diff --git a/content/child/web_url_loader_impl.cc b/content/child/web_url_loader_impl.cc
index 3b31280df50f09dca65106223818b3b9d3ec91b1..15a5a470cf4251095e34ff0bdd09c865856b2778 100644
--- a/content/child/web_url_loader_impl.cc
+++ b/content/child/web_url_loader_impl.cc
@@ -602,11 +602,16 @@ void WebURLLoaderImpl::Context::Start(const WebURLRequest& request,
   // PlzNavigate: during navigation, the renderer should request a stream which
   // contains the body of the response. The network request has already been
   // made by the browser.
+  mojo::ScopedDataPipeConsumerHandle consumer_handle;
   if (stream_override_.get()) {
     CHECK(IsBrowserSideNavigationEnabled());
     DCHECK(!sync_load_response);
     DCHECK_NE(WebURLRequest::kFrameTypeNone, request.GetFrameType());
-    resource_request->resource_body_stream_url = stream_override_->stream_url;
+    if (stream_override_->consumer_handle.is_valid()) {
+      consumer_handle = std::move(stream_override_->consumer_handle);
+    } else {
+      resource_request->resource_body_stream_url = stream_override_->stream_url;
+    }
   }
 
   // PlzNavigate: Invalid renderer main resource requests are rejected by the
@@ -641,7 +646,8 @@ void WebURLLoaderImpl::Context::Start(const WebURLRequest& request,
       std::move(resource_request), request.RequestorID(), task_runner_,
       extra_data->frame_origin(),
       base::MakeUnique<WebURLLoaderImpl::RequestPeerImpl>(this),
-      request.GetLoadingIPCType(), url_loader_factory_);
+      request.GetLoadingIPCType(), url_loader_factory_,
+      std::move(consumer_handle));
 
   if (defers_loading_ != NOT_DEFERRING)
     resource_dispatcher_->SetDefersLoading(request_id_, true);
@@ -808,6 +814,15 @@ void WebURLLoaderImpl::Context::OnReceivedData(
   if (!client_)
     return;
 
+  if (stream_override_.get()) {
+    // Since ResourceDispatcher::ContinueForNavigation called OnComplete

[jam, 2017/04/12 20:49:17]

nit: i would put this inside the next if statement, as only then is data pipe
being used

[scottmg, 2017/04/12 20:51:38]

Should be if (a&&b) anyway, fixed.

+    // immediately, it didn't have the size of the resource immediately. So as
+    // data is read off the data pipe, keep track of how much we're reading.
+    if (stream_override_->stream_url.is_empty()) {
+      stream_override_->total_transferred += data_length;
+    }
+  }
+
   TRACE_EVENT_WITH_FLOW0(
       "loading", "WebURLLoaderImpl::Context::OnReceivedData",
       this, TRACE_EVENT_FLAG_FLOW_IN | TRACE_EVENT_FLAG_FLOW_OUT);
@@ -850,6 +865,14 @@ void WebURLLoaderImpl::Context::OnCompletedRequest(
     const base::TimeTicks& completion_time,
     int64_t total_transfer_size,
     int64_t encoded_body_size) {
+  if (stream_override_.get()) {
+    if (stream_override_->stream_url.is_empty()) {
+      // TODO(kinuko|scottmg|jam): This is wrong. https://crbug.com/598073.

[jam, 2017/04/12 20:49:17]

nit: 598073 is for network service, while this code is for plznavigate. so i'd
either take out that bug or make a new one to track this

[scottmg, 2017/04/12 20:51:38]

Put it on the data pipe one, 705744.

+      total_transfer_size = stream_override_->total_transferred;
+      encoded_body_size = stream_override_->total_transferred;
+    }
+  }
+
   if (ftp_listing_delegate_) {
     ftp_listing_delegate_->OnCompletedRequest();
     ftp_listing_delegate_.reset(NULL);