Begin to enable extension APIs in Extension Service Worker.

extensions/browser/extension_service_worker_message_filter.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 "extensions/browser/extension_service_worker_message_filter.h"
+
+#include "extensions/browser/extension_function_dispatcher.h"
+#include "extensions/common/extension_messages.h"
+
+namespace extensions {
+
+ExtensionServiceWorkerMessageFilter::ExtensionServiceWorkerMessageFilter(
+    int render_process_id,
+    content::BrowserContext* context)
+    : content::BrowserMessageFilter(ExtensionWorkerMsgStart),
+      render_process_id_(render_process_id),
+      browser_context_(context),
+      dispatcher_(new ExtensionFunctionDispatcher(context)) {}
+
+ExtensionServiceWorkerMessageFilter::~ExtensionServiceWorkerMessageFilter() {
+  DCHECK_CURRENTLY_ON(content::BrowserThread::IO);
+}
+
+void ExtensionServiceWorkerMessageFilter::OverrideThreadForMessage(
+    const IPC::Message& message,
+    content::BrowserThread::ID* thread) {
+  if (message.type() == ExtensionHostMsg_RequestWorker::ID) {
+    *thread = content::BrowserThread::UI;
+  }
+}
+
+bool ExtensionServiceWorkerMessageFilter::OnMessageReceived(
+    const IPC::Message& message) {
+  bool handled = true;
+  IPC_BEGIN_MESSAGE_MAP(ExtensionServiceWorkerMessageFilter, message)
+    IPC_MESSAGE_HANDLER(ExtensionHostMsg_RequestWorker, OnRequestWorker)
+    IPC_MESSAGE_UNHANDLED(handled = false)
+  IPC_END_MESSAGE_MAP()
+  return handled;
+}
+
+void ExtensionServiceWorkerMessageFilter::OnRequestWorker(
+    const ExtensionHostMsg_Request_Params& params) {
+  DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
+  dispatcher_->Dispatch(params, nullptr, render_process_id_);
+}
+
+}  // namespace extensions