Add initial extra info feature

Only the extra profile in profiles is shown, since it is the easiest to
implement.

Bug: twpowertools:93
Change-Id: Ife4f31ee056f74bd478702347d75044b024abf1e
diff --git a/src/common/optionsPrototype.json5 b/src/common/optionsPrototype.json5
index ca38042..0d337b2 100644
--- a/src/common/optionsPrototype.json5
+++ b/src/common/optionsPrototype.json5
@@ -126,6 +126,11 @@
     context: 'experiments',
     killSwitchType: 'experiment',
   },
+  'extrainfo': {
+    defaultValue: false,
+    context: 'experiments',
+    killSwitchType: 'experiment',
+  },
 
   // Internal options:
   'ccdarktheme_switch_enabled': {