ui: Cleanup class/struct forward declarations

net/base/registry_controlled_domains/registry_controlled_domain.h

Index: net/base/registry_controlled_domains/registry_controlled_domain.h
diff --git a/net/base/registry_controlled_domains/registry_controlled_domain.h b/net/base/registry_controlled_domains/registry_controlled_domain.h
index bbe8f0b8145bf1b1c74abbb18de16e5ba959ee95..9e631f6f130f99159bbaaba77b7c5519e3dd935f 100644
--- a/net/base/registry_controlled_domains/registry_controlled_domain.h
+++ b/net/base/registry_controlled_domains/registry_controlled_domain.h
@@ -117,6 +117,7 @@
 
 #include <string>
 
+#include "base/optional.h"
 #include "base/strings/string_piece.h"
 #include "net/base/net_export.h"
 
@@ -199,6 +200,10 @@ NET_EXPORT bool SameDomainOrHost(const GURL& gurl1, const GURL& gurl2,
 NET_EXPORT bool SameDomainOrHost(const url::Origin& origin1,
                                  const url::Origin& origin2,
                                  PrivateRegistryFilter filter);
+// Note: this returns false if |origin2| is not set.
+NET_EXPORT bool SameDomainOrHost(const url::Origin& origin1,
+                                 const base::Optional<url::Origin>& origin2,
+                                 PrivateRegistryFilter filter);
 
 // Finds the length in bytes of the registrar portion of the host in the
 // given GURL.  Returns std::string::npos if the GURL is invalid or has no