New WebContents created via ctrl-click should be in a new process.

content/browser/frame_host/navigator_impl.cc

Index: content/browser/frame_host/navigator_impl.cc
diff --git a/content/browser/frame_host/navigator_impl.cc b/content/browser/frame_host/navigator_impl.cc
index d84e2911945758afaea971eb17377bb6b5d21f83..415f3566164baaf8f9c21a320b160f2a1de52a65 100644
--- a/content/browser/frame_host/navigator_impl.cc
+++ b/content/browser/frame_host/navigator_impl.cc
@@ -781,13 +781,6 @@ void NavigatorImpl::RequestOpenURL(
     params.redirect_chain = redirect_chain;
   params.should_replace_current_entry = should_replace_current_entry;
   params.user_gesture = user_gesture;
-
-  // RequestOpenURL is used only for local frames, so we can get here only if
-  // the navigation is initiated by a frame in the same SiteInstance as this
-  // frame.  Note that navigations on RenderFrameProxies do not use
-  // RequestOpenURL and go through RequestTransferURL instead.
-  params.source_site_instance = current_site_instance;
-
   params.source_render_frame_id = render_frame_host->GetRoutingID();
   params.source_render_process_id = render_frame_host->GetProcess()->GetID();