Issue 3459 - Don't duplicate content type definition

lib/contentPolicy.js

Index: lib/contentPolicy.js
===================================================================
--- a/lib/contentPolicy.js
+++ b/lib/contentPolicy.js
@@ -38,32 +38,30 @@
 var Policy = exports.Policy =
 {
   /**
-   * Set of explicitly supported content types
-   * @type Set.<string>
-   */
-  contentTypes: new Set([
-    "OTHER", "SCRIPT", "IMAGE", "STYLESHEET", "OBJECT", "SUBDOCUMENT", "DOCUMENT",
-    "XMLHTTPREQUEST", "OBJECT_SUBREQUEST", "FONT", "MEDIA", "PING", "ELEMHIDE",
-    "POPUP", "GENERICHIDE", "GENERICBLOCK"
-  ]),
-
-  /**
    * Map of content types reported by Firefox to the respecitve content types
    * used by Adblock Plus. Other content types are simply mapped to OTHER.
    * @type Map.<string,string>
    */
-  contentTypesMap: new Map([
+  contentTypes: new Map(function* ()
+  {
     // Treat navigator.sendBeacon() the same as <a ping>,
     // it's essentially the same concept - merely generalized.
-    ["BEACON", "PING"],
+    yield ["BEACON", "PING"];
 
     // Treat <img srcset> and <picture> the same as other images.
-    ["IMAGESET", "IMAGE"],
+    yield ["IMAGESET", "IMAGE"];
 
     // Treat fetch() the same as XMLHttpRequest,
     // it's essentially the same - merely a more modern API.
-    ["FETCH", "XMLHTTPREQUEST"]
-  ]),
+    yield ["FETCH", "XMLHTTPREQUEST"];
+
+    // Everything else is mapped to itself
+    for (let contentType of ["OTHER", "SCRIPT", "IMAGE", "STYLESHEET", "OBJECT",
+                             "SUBDOCUMENT", "DOCUMENT", "XMLHTTPREQUEST",
+                             "OBJECT_SUBREQUEST", "FONT", "MEDIA", "PING",
+                             "ELEMHIDE", "POPUP", "GENERICHIDE", "GENERICBLOCK"])
+      yield [contentType, contentType];
+  }()),
 
   /**
    * Set of content types that aren't associated with a visual document area
@@ -85,9 +83,6 @@
    */
   init: function()
   {
-    for (let contentType of this.contentTypes)
-      this.contentTypesMap.set(contentType, contentType);
-
     // whitelisted URL schemes
     for (let scheme of Prefs.whitelistschemes.toLowerCase().split(" "))
       this.whitelistSchemes.add(scheme);
@@ -147,7 +142,7 @@
       return response(true, false);
 
     // Interpret unknown types as "other"
-    contentType = this.contentTypesMap.get(contentType) || "OTHER";
+    contentType = this.contentTypes.get(contentType) || "OTHER";
 
     let wndLocation = frames[0].location;
     let docDomain = getHostname(wndLocation);