[mojo] Enable ServiceRegistryImpl to override remote services

content/common/mojo/service_registry_impl.cc

 // Copyright 2014 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/mojo/service_registry_impl.h"
 
 #include <utility>
 
 #include "mojo/common/common_type_converters.h"
 
@@ skipping 21 matching lines @@
   CHECK(!remote_provider_);
   remote_provider_ = std::move(service_provider);
   while (!pending_connects_.empty()) {
     remote_provider_->ConnectToService(
         mojo::String::From(pending_connects_.front().first),
         mojo::ScopedMessagePipeHandle(pending_connects_.front().second));
     pending_connects_.pop();
   }
 }
 
-void ServiceRegistryImpl::AddService(
-    const std::string& service_name,
-    const base::Callback<void(mojo::ScopedMessagePipeHandle)> service_factory) {
+void ServiceRegistryImpl::AddServiceOverride(const std::string& service_name,
+                                             const ServiceFactory& factory) {
+  service_overrides_[service_name] = factory;
+}
+
+void ServiceRegistryImpl::AddService(const std::string& service_name,
+                                     const ServiceFactory service_factory) {
   service_factories_[service_name] = service_factory;
 }
 
 void ServiceRegistryImpl::RemoveService(const std::string& service_name) {
   service_factories_.erase(service_name);
 }
 
 void ServiceRegistryImpl::ConnectToRemoteService(
     const base::StringPiece& service_name,
     mojo::ScopedMessagePipeHandle handle) {
+  auto override_it = service_overrides_.find(service_name.as_string());
+  if (override_it != service_overrides_.end()) {
+    override_it->second.Run(std::move(handle));
+    return;
+  }
+
   if (!remote_provider_) {
     pending_connects_.push(
         std::make_pair(service_name.as_string(), handle.release()));
     return;
   }
   remote_provider_->ConnectToService(
       mojo::String::From(service_name.as_string()), std::move(handle));
 }
 
 bool ServiceRegistryImpl::IsBound() const {
   return binding_.is_bound();
 }
 
 base::WeakPtr<ServiceRegistry> ServiceRegistryImpl::GetWeakPtr() {
   return weak_factory_.GetWeakPtr();
 }
 
 void ServiceRegistryImpl::ConnectToService(
     const mojo::String& name,
     mojo::ScopedMessagePipeHandle client_handle) {
-  std::map<std::string,
-           base::Callback<void(mojo::ScopedMessagePipeHandle)> >::iterator it =
-      service_factories_.find(name);
+  auto it = service_factories_.find(name);
   if (it == service_factories_.end())
     return;
 
   // It's possible and effectively unavoidable that under certain conditions
   // an invalid handle may be received. Don't invoke the factory in that case.
   if (!client_handle.is_valid()) {
     DVLOG(2) << "Invalid pipe handle for " << name << " interface request.";
     return;
   }
 
   it->second.Run(std::move(client_handle));
 }
 
 void ServiceRegistryImpl::OnConnectionError() {
   binding_.Close();
 }
 
 }  // namespace content