Introduce ServiceWorkerNavigationPreload feature name

content/public/common/content_features.cc

Index: content/public/common/content_features.cc
diff --git a/content/public/common/content_features.cc b/content/public/common/content_features.cc
index 426ef7b0cfc8cd1469912ab7c95081d575de0bab..61f06a33c5602a055c9f1ca425f766d187db5f2b 100644
--- a/content/public/common/content_features.cc
+++ b/content/public/common/content_features.cc
@@ -153,6 +153,12 @@ const base::Feature kPepper3DImageChromium{"Pepper3DImageChromium",
 const base::Feature kRenderingPipelineThrottling{
     "RenderingPipelineThrottling", base::FEATURE_ENABLED_BY_DEFAULT};
 
+// Navigation preload feature of service workers.
+// TODO(horo): Revise link when this lands in the spec:
+// https://github.com/w3c/ServiceWorker/pull/983/files
+const base::Feature kServiceWorkerNavigationPreload{
+    "ServiceWorkerNavigationPreload", base::FEATURE_DISABLED_BY_DEFAULT};
+
 // Scrolls to compensate for layout movements (bit.ly/scroll-anchoring).
 const base::Feature kScrollAnchoring{"ScrollAnchoring",
                                      base::FEATURE_DISABLED_BY_DEFAULT};