Remove support for the keygen tag

chrome/app/settings_strings.grdp

Index: chrome/app/settings_strings.grdp
diff --git a/chrome/app/settings_strings.grdp b/chrome/app/settings_strings.grdp
index ca3454a9ef39aaf99fcb814c7e4cdde4ff07a095..430a5bfc0a3eace875fdf2df97a022177aa3b8d8 100644
--- a/chrome/app/settings_strings.grdp
+++ b/chrome/app/settings_strings.grdp
@@ -1728,9 +1728,6 @@
   <message name="IDS_SETTINGS_SITE_SETTINGS_LOCATION" desc="Label for the location site settings.">
     Location
   </message>
-  <message name="IDS_SETTINGS_SITE_SETTINGS_KEYGEN" desc="Label for the key generation site settings.">
-    Key generation
-  </message>
   <message name="IDS_SETTINGS_SITE_SETTINGS_MIC" desc="Label for the microphone site settings.">
     Microphone
   </message>
@@ -1836,15 +1833,6 @@
   <message name="IDS_SETTINGS_SITE_SETTINGS_HANDLERS_BLOCKED" desc="The block label for protocol handlers in site settings.">
     Do not allow any site to handle protocols
   </message>
-  <message name="IDS_SETTINGS_SITE_SETTINGS_KEYGEN_ALLOW" desc="The allow label for keygen in site settings.">
-    Allow all sites to use key generation in forms
-  </message>
-  <message name="IDS_SETTINGS_SITE_SETTINGS_KEYGEN_BLOCK" desc="The block label for key generation in site settings.">
-    Do not allow any site to use key generation in forms
-  </message>
-  <message name="IDS_SETTINGS_SITE_SETTINGS_KEYGEN_BLOCK_RECOMMENDED" desc="The block label for key generation in site settings (with the 'recommended' suffix).">
-    Do not allow any site to use key generation in forms (recommended)
-  </message>
   <message name="IDS_SETTINGS_SITE_SETTINGS_AUTOMATIC_DOWNLOAD_ASK" desc="The allow label for automatic download in site settings.">
     Ask when a site tries to download files automatically after the first file
   </message>