PlzNavigate: AppCache support.

content/browser/appcache/appcache_backend_impl.h

Index: content/browser/appcache/appcache_backend_impl.h
diff --git a/content/browser/appcache/appcache_backend_impl.h b/content/browser/appcache/appcache_backend_impl.h
index e7f9b84eb288987c13a37f758f7c0273c6a08d51..b2aad33c00048426dfcae880f351ee7e110898a5 100644
--- a/content/browser/appcache/appcache_backend_impl.h
+++ b/content/browser/appcache/appcache_backend_impl.h
@@ -66,6 +66,12 @@ class CONTENT_EXPORT AppCacheBackendImpl {
   std::unique_ptr<AppCacheHost> TransferHostOut(int host_id);
   void TransferHostIn(int new_host_id, std::unique_ptr<AppCacheHost> host);
 
+  // PlzNaviate
+  // The AppCacheHost is precreated by the AppCacheNavigationHandleCore class
+  // when a navigation is initiated. We register the host with the backend in
+  // this function and ignore registrations for this host id from the renderer.
+  void RegisterPrecreatedHost(std::unique_ptr<AppCacheHost> host);
+
  private:
   AppCacheServiceImpl* service_;
   AppCacheFrontend* frontend_;