Add a feature flag for network service and about:flags entry for it.

content/browser/service_worker/service_worker_request_handler.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/browser/service_worker/service_worker_request_handler.h"
 
 #include <string>
 #include <utility>
 
 #include "base/command_line.h"
 #include "base/macros.h"
 #include "content/browser/loader/url_loader_request_handler.h"
 #include "content/browser/service_worker/service_worker_context_core.h"
 #include "content/browser/service_worker/service_worker_context_wrapper.h"
 #include "content/browser/service_worker/service_worker_navigation_handle_core.h"
 #include "content/browser/service_worker/service_worker_provider_host.h"
 #include "content/browser/service_worker/service_worker_registration.h"
 #include "content/browser/service_worker/service_worker_url_request_job.h"
 #include "content/common/resource_request_body_impl.h"
 #include "content/common/service_worker/service_worker_types.h"
 #include "content/common/service_worker/service_worker_utils.h"
 #include "content/public/browser/resource_context.h"
 #include "content/public/common/browser_side_navigation_policy.h"
 #include "content/public/common/child_process_host.h"
+#include "content/public/common/content_features.h"
 #include "content/public/common/content_switches.h"
 #include "content/public/common/origin_util.h"
 #include "ipc/ipc_message.h"
 #include "net/base/url_util.h"
 #include "net/url_request/url_request.h"
 #include "net/url_request/url_request_interceptor.h"
 #include "storage/browser/blob/blob_storage_context.h"
 
 namespace content {
 
@@ skipping 88 matching lines @@
     ServiceWorkerNavigationHandleCore* navigation_handle_core,
     storage::BlobStorageContext* blob_storage_context,
     bool skip_service_worker,
     ResourceType resource_type,
     RequestContextType request_context_type,
     RequestContextFrameType frame_type,
     bool is_parent_frame_secure,
     scoped_refptr<ResourceRequestBodyImpl> body,
     const base::Callback<WebContents*(void)>& web_contents_getter) {
   DCHECK(IsBrowserSideNavigationEnabled() &&
-         base::CommandLine::ForCurrentProcess()->HasSwitch(
-             switches::kEnableNetworkService));
+         base::FeatureList::IsEnabled(features::kNetworkService));

[Alexei Svitkine (slow), 2017/06/29 13:58:24]

NIt: Seems better to have these as separate DCHECK()'s.

[jam, 2017/06/30 17:21:18]

since I'm just changing flag->feature, I'll leave it to how the original author
preferred to write it.

   DCHECK(navigation_handle_core);
 
   // Create the handler even for insecure HTTP since it's used in the
   // case of redirect to HTTPS.
   if (!resource_request.url.SchemeIsHTTPOrHTTPS() &&
       !OriginCanAccessServiceWorkers(resource_request.url)) {
     return nullptr;
   }
 
   if (!navigation_handle_core->context_wrapper() ||
@@ skipping 150 matching lines @@
     ResourceType resource_type)
     : context_(context),
       provider_host_(provider_host),
       blob_storage_context_(blob_storage_context),
       resource_type_(resource_type),
       old_process_id_(0),
       old_provider_id_(kInvalidServiceWorkerProviderId) {
 }
 
 }  // namespace content