Support Service Worker NavigationPreload with PlzNavigate.

content/public/browser/render_process_host.h

Index: content/public/browser/render_process_host.h
diff --git a/content/public/browser/render_process_host.h b/content/public/browser/render_process_host.h
index aa7a553c46538962ec04dc01942a61c78e2f6b07..fce309cbfa3c0553cd27b5e0f1f7c60a7bbf0f00 100644
--- a/content/public/browser/render_process_host.h
+++ b/content/public/browser/render_process_host.h
@@ -334,6 +334,11 @@ class CONTENT_EXPORT RenderProcessHost : public IPC::Sender,
   // MockRenderProcessHost usage in tests.
   virtual mojom::Renderer* GetRendererInterface() = 0;
 
+  // Returns the ResourceMessageFilter of the process. This is used to send
+  // service worker navigation requests when PlzNavigate is enabled. Only
+  // exposed here to support MockRenderProcessHost usage in tests.
+  virtual BrowserMessageFilter* GetResourceMessageFilter() = 0;
+
   // Returns the current number of active views in this process.  Excludes
   // any RenderViewHosts that are swapped out.
   size_t GetActiveViewCount();