Teach EmbeddedWorkerInstance to create a process when it needs one.

content/renderer/service_worker/embedded_worker_dispatcher.cc

 // Copyright 2013 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/service_worker/embedded_worker_dispatcher.h"
 
 #include "base/memory/scoped_ptr.h"
 #include "base/strings/string16.h"
 #include "base/strings/utf_string_conversions.h"
 #include "content/child/child_process.h"
@@ skipping 45 matching lines @@
   RenderThreadImpl::current()->thread_safe_sender()->Send(
       new EmbeddedWorkerHostMsg_WorkerStopped(embedded_worker_id));
   workers_.Remove(embedded_worker_id);
 }
 
 void EmbeddedWorkerDispatcher::OnStartWorker(int embedded_worker_id,
                                              int64 service_worker_version_id,
                                              const GURL& service_worker_scope,
                                              const GURL& script_url) {
   DCHECK(!workers_.Lookup(embedded_worker_id));
+  RenderThread::Get()->EnsureWebKitInitialized();

[Jeffrey Yasskin, 2014/04/25 04:40:33]

This is needed if the SW is the first code run in a new process.

   scoped_ptr<WorkerWrapper> wrapper(new WorkerWrapper(
       blink::WebEmbeddedWorker::create(
           new EmbeddedWorkerContextClient(
               embedded_worker_id,
               service_worker_version_id,
               service_worker_scope,
               script_url),
           NULL)));
 
   blink::WebEmbeddedWorkerStartData start_data;
@@ skipping 12 matching lines @@
     return;
   }
 
   // This should eventually call WorkerContextDestroyed. (We may need to post
   // a delayed task to forcibly abort the worker context if we find it
   // necessary)
   wrapper->worker()->terminateWorkerContext();
 }
 
 }  // namespace content