[runtime] [proxy] removing JSFunctionProxy and related code.

src/factory.h

Index: src/factory.h
diff --git a/src/factory.h b/src/factory.h
index e1f24c87f878a8416ad8efc16d89d62f9ceb8a2c..a456fa2cae15f592d719d4b4ded9a2b902f7ddc0 100644
--- a/src/factory.h
+++ b/src/factory.h
@@ -481,13 +481,6 @@ class Factory final {
   Handle<JSProxy> NewJSProxy(Handle<JSReceiver> target,
                              Handle<JSReceiver> handler);
 
-  // Allocates a Harmony function proxy.
-  Handle<JSProxy> NewJSFunctionProxy(Handle<JSReceiver> target,
-                                     Handle<JSReceiver> handler,
-                                     Handle<JSReceiver> call_trap,
-                                     Handle<Object> construct_trap,
-                                     Handle<Object> prototype);
-
   // Reinitialize an JSGlobalProxy based on a constructor.  The object
   // must have the same size as objects allocated using the
   // constructor.  The object is reinitialized and behaves as an