Add IPC stubs between browser and ServiceWorker's worker context in the child process

content/common/service_worker_interfaces.cc

Index: content/common/service_worker_interfaces.cc
diff --git a/tools/json_schema_compiler/test/idl_namespace_specific_implement.idl b/content/common/service_worker_interfaces.cc
similarity index 58%
copy from tools/json_schema_compiler/test/idl_namespace_specific_implement.idl
copy to content/common/service_worker_interfaces.cc
index 99b65ac50a53fcf5cd73cd38ba01a0be1515b598..7e204ab58a41da8e6b6dd0815b21114639c756d8 100644
--- a/tools/json_schema_compiler/test/idl_namespace_specific_implement.idl
+++ b/content/common/service_worker_interfaces.cc
@@ -2,9 +2,11 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// Tests the case of a namespace with specific implemented file.
+#include "content/common/service_worker_interfaces.h"
 
-[implemented_in="idl_namespace_specific_implement.idl"]
-namespace idl_namespace_specific_implement {
+namespace content {
 
-};
+ServiceWorkerFetchRequest::ServiceWorkerFetchRequest() {}
+ServiceWorkerFetchRequest::~ServiceWorkerFetchRequest() {}
+
+}  // namespace content