Add DISABLE_TCP_TRANSPORT flag in the Transport API.

remoting/host/plugin/policy_hack/nat_policy.cc

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Most of this code is copied from:
 //   src/chrome/browser/policy/asynchronous_policy_loader.{h,cc}
 
 #include "remoting/host/plugin/policy_hack/nat_policy.h"
 
 #include "base/bind.h"
@@ skipping 87 matching lines @@
     if (new_policy->Get(kNatPolicyName, &value) &&
         value->IsType(base::Value::TYPE_BOOLEAN)) {
       CHECK(value->GetAsBoolean(&new_nat_enabled_state));
     }
   }
 
   if (!first_state_published_ ||
       (new_nat_enabled_state != current_nat_enabled_state_)) {
     first_state_published_ = true;
     current_nat_enabled_state_ = new_nat_enabled_state;
+    LOG(ERROR) << "Calling callback";
     nat_enabled_cb_.Run(current_nat_enabled_state_);
   }
 }
 
 }  // namespace policy_hack
 }  // namespace remoting