Merge changes Ife0cb7fb,Id1a0a442,Idaafa178,I204ed759

* changes:
  Document that being a code owner doesn't grant the user permissions to approve
  ChangedFiles: Correct comment about initial commits
  Document that per-file lines should not contain additional spaces
  Document why non-resolvable emails are reject with a generic message
diff --git a/ui/owner-requirement.js b/ui/owner-requirement.js
index c15fcf3..f456e65 100644
--- a/ui/owner-requirement.js
+++ b/ui/owner-requirement.js
@@ -55,6 +55,9 @@
         gr-button {
           padding-left: var(--spacing-m);
         }
+        gr-button::part(paper-button) {
+          padding: 0 var(--spacing-s);
+        }
         a {
           text-decoration: none;
         }