node: remove bad fn call and check

These two lines exist because of a screw up on my part while combining
MakeCallback() and MakeDomainCallback().

The reason it never broke core tests is because any paths it would have
broken were rerouted to AsyncWrap::MakeCallback(). The only case that
node::MakeCallback() handles anymore is setImmediate().

Fix: a1da024 "node, async-wrap: remove MakeDomainCallback"
PR-URL: https://github.com/nodejs/io.js/pull/2157
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>

src/node.cc

@@ -1092,8 +1092,6 @@ Handle<Value> MakeCallback(Environment* env,
         return Undefined(env->isolate());
     }
   }
-  env->tick_callback_function()->Call(process, 0, nullptr);
-  CHECK_EQ(env->context(), env->isolate()->GetCurrentContext());
 
   if (try_catch.HasCaught()) {
     return Undefined(env->isolate());