Docserver: Correctly disambiguate between what 'platform' means in a features

chrome/common/extensions/docs/templates/json/permissions.json

 {
   "host-permissions": {
     "channel": "stable",
     "anchor": "host-permissions",
     "name": "[scheme]:[host]/*",
     "partial": "permissions/host_permissions.html",
     "extension_types": ["legacy_packaged_app", "extension", "platform_app"]
   },
   "activeTab": {
     "partial": "permissions/active_tab.html"
   },
   "alwaysOnTopWindows": {
     "partial": "permissions/always_on_top_windows.html"
   },
   "audioCapture": {
     "partial": "permissions/audio_capture.html"
   },
   "background": {
     "partial": "permissions/background.html"
   },
   "chrome://favicon/": {
     "anchor": "favicon",
+    "extension_types": ["extension"],
     "name": "chrome://favicon/",
-    "partial": "permissions/favicon.html",
-    "platforms": ["extension"]
+    "partial": "permissions/favicon.html"
   },
   "clipboardRead": {
     "partial": "permissions/clipboard_read.html"
   },
   "clipboardWrite": {
     "partial": "permissions/clipboard_write.html"
   },
   "experimental": {
     "partial": "permissions/experimental.html"
   },
@@ skipping 21 matching lines @@
   "videoCapture": {
     "partial": "permissions/video_capture.html"
   },
   "webRequestBlocking": {
     "partial": "permissions/web_request_blocking.html"
   },
   "webview": {
     "partial": "permissions/webview.html"
   }
 }