Add a blink InterfaceRegistry.

content/renderer/mojo/blink_interface_registry_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/renderer/mojo/blink_interface_registry_impl.h"
+
+#include <utility>
+
+#include "base/bind.h"
+#include "mojo/public/cpp/system/message_pipe.h"
+#include "services/shell/public/cpp/interface_registry.h"
+
+namespace content {
+namespace {
+
+void ForwardToInterfaceFactory(
+    const std::unique_ptr<blink::InterfaceFactory>& factory,
+    mojo::ScopedMessagePipeHandle handle) {
+  factory->onSuccess(std::move(handle));
+}
+
+}  // namespace
+
+BlinkInterfaceRegistryImpl::BlinkInterfaceRegistryImpl(
+    base::WeakPtr<shell::InterfaceRegistry> interface_registry)
+    : interface_registry_(interface_registry) {}
+
+BlinkInterfaceRegistryImpl::~BlinkInterfaceRegistryImpl() = default;
+
+void BlinkInterfaceRegistryImpl::addInterface(
+    const char* name,
+    std::unique_ptr<blink::InterfaceFactory> factory) {
+  if (!interface_registry_)
+    return;
+
+  interface_registry_->AddInterface(
+      name, base::Bind(&ForwardToInterfaceFactory, std::move(factory)));
+}
+
+}  // namespace content