Mac: implement <keygen> support, including adding generated cert to the Keychain.

chrome/app/generated_resources.grd

 <?xml version="1.0" encoding="UTF-8"?>
 
 <!-- This file contains definitions of resources that will be translated for
 each locale. -->
 
 <grit base_dir="." latest_public_release="0" current_release="1"
       source_lang_id="en" enc_check="möl">
   <outputs>
     <output filename="grit/generated_resources.h" type="rc_header">
       <emit emit_type='prepend'></emit>
@@ skipping 2734 matching lines @@
       <message name="IDS_CERT_MANAGER_EXPIRES_COLUMN_LABEL" desc="Label for the expires on column of the certificate tree in the certificate manager">
         Expires On
       </message>
       <message name="IDS_CERT_MANAGER_EMAIL_ADDRESS_COLUMN_LABEL" desc="Label for the email address column of the certificate tree in the certificate manager">
         Email Address
       </message>
       <message name="IDS_CERT_MANAGER_VIEW_CERT_BUTTON" desc="Label for the button in the certificate manager which launches the certificate viewer for the selected certificate">
         &amp;View
       </message>
 
+      <!-- Add Client Certificate Dialog -->
+      <message name="IDS_ADD_CERT_DIALOG_ADD" desc="Title of the button that adds the certificate in the Add Client Certificate dialog">
+        Add Certificate
+      </message>
+      <message name="IDS_ADD_CERT_FAILURE_TITLE" desc="Title of add-certificate error dialog">
+        Client Certificate Error
+      </message>
+      <message name="IDS_ADD_CERT_ERR_INVALID_CERT" desc="Error message when the server returns an invalid client certificate after key generation">
+        The server returned an invalid client certificate.
+      </message>
+      <message name="IDS_ADD_CERT_ERR_FAILED" desc="Generic error message for a failure to add the generated certificate to the cert store/keychain">
+        There was an error while trying to store the client certificate.
+      </message>
+
       <!-- Basic Auth Dialog -->
       <message name="IDS_LOGIN_DIALOG_TITLE" desc="String to be displayed in the title bar of the login prompt dialog">
         Authentication Required
       </message>
       <message name="IDS_LOGIN_DIALOG_DESCRIPTION" desc="String to be displayed in the login prompt dialog to explain what the user needs to do">
         The server <ph name="DOMAIN">$1<ex>google.com</ex></ph> at <ph name="REALM">$2<ex>site name</ex></ph> requires a username and password.
       </message>
       <message name="IDS_LOGIN_DIALOG_DESCRIPTION_NO_REALM" desc="String to be displayed in the login prompt dialog to explain what the user needs to do">
         The server <ph name="DOMAIN">$1<ex>google.com</ex></ph> requires a username and password.
       </message>
@@ skipping 3972 matching lines @@
       <message name="IDS_NOTIFICATION_PANEL_TITLE" desc="Text for the title of the notification panel.">
         Notifications
       </message>
     </if>
      <message name="IDS_BOOKMARK_BAR_IMPORT_LINK" desc="text shown for importing ">
        Import bookmarks now...
      </message>
     </messages>
   </release>
 </grit>