listanchors.js: Match both dlang.org and docarchives.dlang.io in version selector

Currently, when you view an archived version of dlang.org site via
docarchives.dlang.io, you can (1) only go further back in time, and (2)
the master/stable options only refer to the current archived version.

This change lays down the foundations to allow going both forwards and
backwards between dlang versions, and the master/stable options now
point at the main dlang.org site, so you can go from whatever archived
version to mainline in one click.

Author: ibuclaw

js/listanchors.js

@@ -66,45 +66,43 @@ function addVersionSelector() {
       return {
         name: e,
         url: "https://docarchives.dlang.io/v" + e + ".0/" + currentRoot + ddocModuleURL,
-        selected: false,
       };
   });
 
-  var rootURL = location.href.split(/\/(phobos|library|spec)(-prerelease)?/)[0]
   var onlineVersions;
   if (isSpec) {
     onlineVersions = [{
       name: "master",
-      url: rootURL + "/spec/" + ddocModuleURL,
+      url: "https://dlang.org/spec/" + ddocModuleURL,
     }];
   } else {
     onlineVersions = [{
       name: "master",
-      url: rootURL + "/phobos-prerelease/" + ddocModuleURL,
+      url: "https://dlang.org/phobos-prerelease/" + ddocModuleURL,
     },{
       name: "master (ddox)",
-      url: rootURL + "/library-prerelease/" + ddoxModuleURL,
+      url: "https://dlang.org/library-prerelease/" + ddoxModuleURL,
     },{
       name: "stable",
-      url: rootURL + "/phobos/" + ddocModuleURL,
+      url: "https://dlang.org/phobos/" + ddocModuleURL,
     },{
       name: "stable (ddox)",
-      url: rootURL + "/library/" + ddoxModuleURL,
+      url: "https://dlang.org/library/" + ddoxModuleURL,
     }];
   }
 
   // set the current URL as selected
   var currentURL = location.href.split(/[#?]/)[0];
-  onlineVersions.forEach(function(v, i) {
-    onlineVersions[i].selected = v.url === currentURL;
+  var versions = onlineVersions.concat(archivedVersions);
+  versions.forEach(function(v, i) {
+    versions[i].selected = v.url === currentURL;
   });
   // Don't show the option chooser if the page hasn't been recognized
   // For example, Ddox symbol pages are currently not supported
-  if (onlineVersions.filter(function(v){return v.selected}).length === 0)
+  if (versions.filter(function(v){return v.selected}).length === 0)
     return;
 
   // build select box of all versions and append to current DOM
-  var versions = onlineVersions.concat(archivedVersions);
   var options = versions.map(function(e, i){
     return "<option value='" + i + "'" + (e.selected ? "selected" : "") + ">" + e.name + "</option>";
   });