Move the `privacy` extension API out of experimental.

chrome/app/generated_resources.grd

Index: chrome/app/generated_resources.grd
diff --git a/chrome/app/generated_resources.grd b/chrome/app/generated_resources.grd
index ae685f866bf4ebf99aadc7bb975726b0c0b9be26..0943e41c8fabe03f4e9c10db5312580b3e080922 100644
--- a/chrome/app/generated_resources.grd
+++ b/chrome/app/generated_resources.grd
@@ -4034,6 +4034,9 @@ Update checks have repeatedly failed for the extension "<ph name="EXTENSION_NAME
       <message name="IDS_EXTENSION_PROMPT_WARNING_CONTENT_SETTINGS" desc="Permission string for access to content settings.">
         Settings that specify whether websites can use features such as cookies, JavaScript, and plug-ins
       </message>
+      <message name="IDS_EXTENSION_PROMPT_WARNING_PRIVACY" desc="Permission string for access to privacy settings.">
+        Privacy-related settings.
+      </message>
 
       <!-- Extension/App error messages -->
       <message name="IDS_EXTENSION_CANT_GET_ABSOLUTE_PATH" desc="Warning displayed in pack dialog when the absolute path to the extension directory can not be found.">