[Extensions] Begin making Extension port initialization asynchronous

extensions/renderer/runtime_custom_bindings.h

Index: extensions/renderer/runtime_custom_bindings.h
diff --git a/extensions/renderer/runtime_custom_bindings.h b/extensions/renderer/runtime_custom_bindings.h
index 17e96bbaf793f03b424c7c5144c145ea59dbdb4b..7b8f077617574b538285608d7e411958d42177dd 100644
--- a/extensions/renderer/runtime_custom_bindings.h
+++ b/extensions/renderer/runtime_custom_bindings.h
@@ -18,12 +18,6 @@ class RuntimeCustomBindings : public ObjectBackedNativeHandler {
 
   ~RuntimeCustomBindings() override;
 
-  // Creates a new messaging channel to the given extension.
-  void OpenChannelToExtension(const v8::FunctionCallbackInfo<v8::Value>& args);
-
-  // Creates a new messaging channels for the specified native application.
-  void OpenChannelToNativeApp(const v8::FunctionCallbackInfo<v8::Value>& args);
-
  private:
   void GetManifest(const v8::FunctionCallbackInfo<v8::Value>& args);
   void GetExtensionViews(const v8::FunctionCallbackInfo<v8::Value>& args);