Add a DevTools warning for a missing subjectAltName

components/security_state/core/security_state.h

Index: components/security_state/core/security_state.h
diff --git a/components/security_state/core/security_state.h b/components/security_state/core/security_state.h
index 7de0fa7437b5d1961a67425d30069ce050207ce7..480d25ae6f09181379305a1503b2b06681b42119 100644
--- a/components/security_state/core/security_state.h
+++ b/components/security_state/core/security_state.h
@@ -142,6 +142,10 @@ struct SecurityInfo {
 
   // True if the page displayed credit card field on an HTTP page.
   bool displayed_credit_card_field_on_http;
+
+  // True if the server's certificate does not contain a
+  // subjectAltName extension with a domain name or IP address.
+  bool cert_missing_subject_alt_name;
 };
 
 // Contains the security state relevant to computing the SecurityInfo