deleted file mode 100644
--- a/browser/modules/CastingApps.jsm
+++ /dev/null
@@ -1,162 +0,0 @@
-// -*- Mode: js; tab-width: 2; indent-tabs-mode: nil; js2-basic-offset: 2; js2-skip-preprocessor-directives: t; -*-
-/* This Source Code Form is subject to the terms of the Mozilla Public
- * License, v. 2.0. If a copy of the MPL was not distributed with this file,
- * You can obtain one at http://mozilla.org/MPL/2.0/. */
-"use strict";
-var EXPORTED_SYMBOLS = ["CastingApps"];
-
-ChromeUtils.import("resource://gre/modules/Services.jsm");
-ChromeUtils.import("resource://gre/modules/SimpleServiceDiscovery.jsm");
-
-
-var CastingApps = {
-  _sendEventToVideo(element, data) {
-    let event = element.ownerDocument.createEvent("CustomEvent");
-    event.initCustomEvent("media-videoCasting", false, true, JSON.stringify(data));
-    element.dispatchEvent(event);
-  },
-
-  makeURI(url, charset, baseURI) {
-    return Services.io.newURI(url, charset, baseURI);
-  },
-
-  getVideo(element) {
-    if (!element) {
-      return null;
-    }
-
-    let extensions = SimpleServiceDiscovery.getSupportedExtensions();
-    let types = SimpleServiceDiscovery.getSupportedMimeTypes();
-
-    // Grab the poster attribute from the <video>
-    let posterURL = element.poster;
-
-    // First, look to see if the <video> has a src attribute
-    let sourceURL = element.src;
-
-    // If empty, try the currentSrc
-    if (!sourceURL) {
-      sourceURL = element.currentSrc;
-    }
-
-    if (sourceURL) {
-      // Use the file extension to guess the mime type
-      let sourceURI = this.makeURI(sourceURL, null, this.makeURI(element.baseURI));
-      if (this.allowableExtension(sourceURI, extensions)) {
-        return { element, source: sourceURI.spec, poster: posterURL, sourceURI};
-      }
-    }
-
-    // Next, look to see if there is a <source> child element that meets
-    // our needs
-    let sourceNodes = element.getElementsByTagName("source");
-    for (let sourceNode of sourceNodes) {
-      let sourceURI = this.makeURI(sourceNode.src, null, this.makeURI(sourceNode.baseURI));
-
-      // Using the type attribute is our ideal way to guess the mime type. Otherwise,
-      // fallback to using the file extension to guess the mime type
-      if (this.allowableMimeType(sourceNode.type, types) || this.allowableExtension(sourceURI, extensions)) {
-        return { element, source: sourceURI.spec, poster: posterURL, sourceURI, type: sourceNode.type };
-      }
-    }
-
-    return null;
-  },
-
-  sendVideoToService(videoElement, service) {
-    if (!service)
-      return;
-
-    let video = this.getVideo(videoElement);
-    if (!video) {
-      return;
-    }
-
-    // Make sure we have a player app for the given service
-    let app = SimpleServiceDiscovery.findAppForService(service);
-    if (!app)
-      return;
-
-    video.title = videoElement.ownerGlobal.top.document.title;
-    if (video.element) {
-      // If the video is currently playing on the device, pause it
-      if (!video.element.paused) {
-        video.element.pause();
-      }
-    }
-
-    app.stop(() => {
-      app.start(started => {
-        if (!started) {
-          Cu.reportError("CastingApps: Unable to start app");
-          return;
-        }
-
-        app.remoteMedia(remoteMedia => {
-          if (!remoteMedia) {
-            Cu.reportError("CastingApps: Failed to create remotemedia");
-            return;
-          }
-
-          this.session = {
-            service,
-            app,
-            remoteMedia,
-            data: {
-              title: video.title,
-              source: video.source,
-              poster: video.poster
-            },
-            videoRef: Cu.getWeakReference(video.element)
-          };
-        }, this);
-      });
-    });
-  },
-
-  getServicesForVideo(videoElement) {
-    let video = this.getVideo(videoElement);
-    if (!video) {
-      return {};
-    }
-
-    let filteredServices = SimpleServiceDiscovery.services.filter(service => {
-      return this.allowableExtension(video.sourceURI, service.extensions) ||
-             this.allowableMimeType(video.type, service.types);
-    });
-
-    return filteredServices;
-  },
-
-  getServicesForMirroring() {
-    return SimpleServiceDiscovery.services.filter(service => service.mirror);
-  },
-
-  // RemoteMedia callback API methods
-  onRemoteMediaStart(remoteMedia) {
-    if (!this.session) {
-      return;
-    }
-
-    remoteMedia.load(this.session.data);
-
-    let video = this.session.videoRef.get();
-    if (video) {
-      this._sendEventToVideo(video, { active: true });
-    }
-  },
-
-  onRemoteMediaStop(remoteMedia) {
-  },
-
-  onRemoteMediaStatus(remoteMedia) {
-  },
-
-  allowableExtension(uri, extensions) {
-    return (uri instanceof Ci.nsIURL) && extensions.includes(uri.fileExtension);
-  },
-
-  allowableMimeType(type, types) {
-    return types.includes(type);
-  }
-};

--- a/browser/modules/ContextMenu.jsm
+++ b/browser/modules/ContextMenu.jsm
@@ -10,17 +10,16 @@ var EXPORTED_SYMBOLS = ["ContextMenu"];
 
 Cu.importGlobalProperties(["URL"]);
 
 ChromeUtils.import("resource://gre/modules/Services.jsm");
 ChromeUtils.import("resource://gre/modules/XPCOMUtils.jsm");
 
 XPCOMUtils.defineLazyModuleGetters(this, {
   E10SUtils: "resource://gre/modules/E10SUtils.jsm",
-  CastingApps: "resource:///modules/CastingApps.jsm",
   BrowserUtils: "resource://gre/modules/BrowserUtils.jsm",
   PlacesUIUtils: "resource:///modules/PlacesUIUtils.jsm",
   findCssSelector: "resource://gre/modules/css-selector.js",
   SpellCheckHelper: "resource://gre/modules/InlineSpellChecker.jsm",
   LoginManagerContent: "resource://gre/modules/LoginManagerContent.jsm",
   WebNavigationFrames: "resource://gre/modules/WebNavigationFrames.jsm",
   PrivateBrowsingUtils: "resource://gre/modules/PrivateBrowsingUtils.jsm",
   InlineSpellCheckerContent: "resource://gre/modules/InlineSpellCheckerContent.jsm",