show 'Open Original' for share links

Author: jpolitz

src/web/css/editor.css

@@ -1925,3 +1925,6 @@ button.controller {
   margin: auto;
   display: block;
 }
+.hidden {
+  display: none
+}

src/web/editor.html

@@ -64,6 +64,7 @@
   <div id="filemenuContents" class="menuContents" style="display: none; z-index: 8990;">
     <div id="new" class="menuButton"><a href="javascript:void(0)">New</a></div>
     <div id="open" class="menuButton"><a href="javascript:void(0)">Open</a></div>
+    <div id="open-original" class="menuButton disabled hidden"><a href="javascript:void(0)">Open Original</a></div>
     <div id="save" class="menuButton disabled"><a href="javascript:void(0)">Save</a></div>
     <div id="saveas" class="menuButton"><a href="javascript:void(0)">Save a copy</a></div>
     <div id="download" class="menuButton"><a href="javascript:void(0)">Download</a></div>

src/web/js/beforePyret.js

@@ -290,6 +290,20 @@ $(function() {
           id: params["get"]["share"]
         });
       programLoad = api.getSharedFileById(params["get"]["share"]);
+      programLoad.then(function(file) {
+        // NOTE(joe): If the current user doesn't own or have access to this file
+        // (or isn't logged in) this will simply fail with a 401, so we don't do
+        // any further permission checking before showing the link.
+        file.getOriginal().then(function(response) {
+          console.log("Response for original: ", response);
+          var original = $("#open-original").show().off("click");
+          var id = response.result.value;
+          original.removeClass("disabled");
+          original.click(function() {
+            window.open(window.APP_BASE_URL + "/editor#program=" + id, "_blank");
+          });
+        });
+      });
     }
     if(programLoad) {
       programLoad.fail(function(err) {

src/web/js/google-apis/drive.js

@@ -15,6 +15,14 @@ window.createProgramCollectionAPI = function createProgramCollectionAPI(collecti
     function makeSharedFile(googFileObject, fetchFromGoogle) {
       return {
         shared: true,
+        getOriginal: function() {
+          var request = gapi.client.drive.properties.get({
+            'fileId': googFileObject.id,
+            'propertyKey': BACKREF_KEY,
+            'visibility': 'PRIVATE'
+          });
+          return request;
+        },
         getContents: function() {
           if(fetchFromGoogle) {
             // NOTE(joe): See https://developers.google.com/drive/v2/web/manage-downloads