Add DCHECK when service handler is missing

content/common/service_manager/service_manager_connection_impl.cc

 // Copyright 2016 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.
 
 #include "content/common/service_manager/service_manager_connection_impl.h"
 
 #include <queue>
 #include <utility>
 #include <vector>
 
@@ skipping 492 matching lines @@
 void ServiceManagerConnectionImpl::RemoveOnConnectHandler(int id) {
   auto it = on_connect_handlers_.find(id);
   DCHECK(it != on_connect_handlers_.end());
   on_connect_handlers_.erase(it);
 }
 
 void ServiceManagerConnectionImpl::CreateService(
     service_manager::mojom::ServiceRequest request,
     const std::string& name) {
   auto it = request_handlers_.find(name);
+  DCHECK(it != request_handlers_.end())
+      << "Can't create service " << name << ". No handler found.";
   if (it != request_handlers_.end())
     it->second.Run(std::move(request));
 }
 
 void ServiceManagerConnectionImpl::OnContextInitialized(
     const service_manager::Identity& identity) {
   identity_ = identity;
 }
 
 void ServiceManagerConnectionImpl::OnConnectionLost() {
@@ skipping 10 matching lines @@
 }
 
 void ServiceManagerConnectionImpl::GetInterface(
     service_manager::mojom::InterfaceProvider* provider,
     const std::string& interface_name,
     mojo::ScopedMessagePipeHandle request_handle) {
   provider->GetInterface(interface_name, std::move(request_handle));
 }
 
 }  // namespace content
-