Introduce Origin-Trial for Service Worker Navigation Preload

content/browser/service_worker/service_worker_version.cc

Index: content/browser/service_worker/service_worker_version.cc
diff --git a/content/browser/service_worker/service_worker_version.cc b/content/browser/service_worker/service_worker_version.cc
index 49294d9b6618cafe268a300463f6464d617057ed..d935a9a0230e5a3dca55caefed24827911c759b0 100644
--- a/content/browser/service_worker/service_worker_version.cc
+++ b/content/browser/service_worker/service_worker_version.cc
@@ -12,6 +12,7 @@
 
 #include "base/command_line.h"
 #include "base/debug/alias.h"
+#include "base/feature_list.h"
 #include "base/guid.h"
 #include "base/location.h"
 #include "base/macros.h"
@@ -46,6 +47,7 @@
 #include "content/public/browser/content_browser_client.h"
 #include "content/public/browser/render_process_host.h"
 #include "content/public/common/content_client.h"
+#include "content/public/common/content_features.h"
 #include "content/public/common/content_switches.h"
 #include "content/public/common/result_codes.h"
 #include "net/http/http_response_headers.h"
@@ -1131,6 +1133,23 @@ void ServiceWorkerVersion::NotifyMainScriptJobCreated(
   main_script_job_created_ = status;
 }
 
+bool ServiceWorkerVersion::IsNavigationPreloadSupported() const {
+  if (base::FeatureList::GetInstance()->IsFeatureOverriddenFromCommandLine(
+          features::kServiceWorkerNavigationPreload.name,
+          base::FeatureList::OVERRIDE_ENABLE_FEATURE)) {
+    return true;
+  }
+  if (!base::FeatureList::IsEnabled(features::kServiceWorkerNavigationPreload))
+    return false;
+  // The origin trial of Navigation Preload started from M57. And the worker
+  // entry in the database written by Chrome (>= M56) must have the
+  // origin_trial_tokens field.
+  if (!origin_trial_tokens_)
+    return false;
+  return base::ContainsKey(*origin_trial_tokens_,
+                           "ServiceWorkerNavigationPreload");
+}
+
 void ServiceWorkerVersion::OnSimpleEventResponse(
     int request_id,
     blink::WebServiceWorkerEventResult result,