Make ProfileIOData's ProxyService fetch PACs with the main URLRequestContext

chrome/browser/profiles/profile_io_data.h

Index: chrome/browser/profiles/profile_io_data.h
diff --git a/chrome/browser/profiles/profile_io_data.h b/chrome/browser/profiles/profile_io_data.h
index 34220799e7415da79a2a9d5f4f394c6cf8b4d0da..4b144947500f67aeb666e62ea5f80e6ebfc92565 100644
--- a/chrome/browser/profiles/profile_io_data.h
+++ b/chrome/browser/profiles/profile_io_data.h
@@ -449,10 +449,16 @@ class ProfileIOData {
   // Virtual interface for subtypes to implement:
   // --------------------------------------------
 
+  // Does any necessary additional configuration of the network delegate,
+  // including composing it with other NetworkDelegates, if needed. By default,
+  // just returns the input NetworkDelegate.
+  virtual std::unique_ptr<net::NetworkDelegate> ConfigureNetworkDelegate(
+      IOThread* io_thread,
+      std::unique_ptr<ChromeNetworkDelegate> chrome_network_delegate) const;
+
   // Does the actual initialization of the ProfileIOData subtype. Subtypes
   // should use the static helper functions above to implement this.
   virtual void InitializeInternal(
-      std::unique_ptr<ChromeNetworkDelegate> chrome_network_delegate,
       ProfileParams* profile_params,
       content::ProtocolHandlerMap* protocol_handlers,
       content::URLRequestInterceptorScopedVector request_interceptors)