Bug 1819082 - Wait for l10n in editcacert dialog. r=Gijs

Use mozSubDialogReady (same as for content subdialogs) as an extra
waiting point.

Differential Revision: https://phabricator.services.mozilla.com/D171127

security/manager/pki/resources/content/editcacert.js

@@ -12,20 +12,15 @@ var gCertDB = Cc["@mozilla.org/security/x509certdb;1"].getService(
  *
  * @type {nsIX509Cert}
  */
-var gCert;
+var gCert = window.arguments[0];
 
-/**
- * onload() handler.
- */
-function onLoad() {
-  gCert = window.arguments[0];
+document.mozSubdialogReady = init();
 
-  document.addEventListener("dialogaccept", onDialogAccept);
-
-  let certMsg = document.getElementById("certmsg");
-  document.l10n.setAttributes(certMsg, "edit-trust-ca", {
-    certName: gCert.commonName,
+async function init() {
+  await new Promise(r => {
+    document.addEventListener("DOMContentLoaded", r, { once: true });
   });
+  document.addEventListener("dialogaccept", onDialogAccept);
 
   let sslCheckbox = document.getElementById("trustSSL");
   sslCheckbox.checked = gCertDB.isCertTrusted(
@@ -40,6 +35,14 @@ function onLoad() {
     Ci.nsIX509Cert.CA_CERT,
     Ci.nsIX509CertDB.TRUSTED_EMAIL
   );
+
+  let certMsg = document.getElementById("certmsg");
+  document.l10n.pauseObserving();
+  document.l10n.setAttributes(certMsg, "edit-trust-ca", {
+    certName: gCert.commonName,
+  });
+  document.l10n.resumeObserving();
+  await document.l10n.translateElements([certMsg]);
 }
 
 /**

security/manager/pki/resources/content/editcacert.xhtml

@@ -10,11 +10,9 @@
 <window data-l10n-id="certmgr-edit-ca-cert2"
         data-l10n-attrs="style"
         xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
-        xmlns:html="http://www.w3.org/1999/xhtml"
-        onload="onLoad();">
+        xmlns:html="http://www.w3.org/1999/xhtml">
 <dialog id="editCaCert"
         buttons="accept,cancel">
-
   <linkset>
     <html:link rel="localization" href="security/certificates/certManager.ftl"/>
   </linkset>
@@ -24,7 +22,7 @@
 
   <description id="certmsg"/>
   <separator/>
-  <description data-l10n-id="certmgr-edit-cert-edit-trust"></description>
+  <description data-l10n-id="certmgr-edit-cert-edit-trust"/>
   <vbox align="start">
     <checkbox data-l10n-id="certmgr-edit-cert-trust-ssl"
               id="trustSSL"/>

toolkit/content/widgets/dialog.js

@@ -350,6 +350,9 @@
       if (this._translationReady) {
         await this._translationReady;
       }
+      if (document.mozSubDialogReady) {
+        await document.mozSubDialogReady;
+      }
 
       let finalStep = () => {
         this._sizeToPreferredSize();