diff -r 000000000000 -r 6474c204b198 toolkit/components/thumbnails/PageThumbsProtocol.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/toolkit/components/thumbnails/PageThumbsProtocol.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,112 @@
+/* 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/. */
+
+/**
+ * PageThumbsProtocol.js
+ *
+ * This file implements the moz-page-thumb:// protocol and the corresponding
+ * channel delivering cached thumbnails.
+ *
+ * URL structure:
+ *
+ * moz-page-thumb://thumbnail?url=http%3A%2F%2Fwww.mozilla.org%2F
+ *
+ * This URL requests an image for 'http://www.mozilla.org/'.
+ */
+
+"use strict";
+
+const Cu = Components.utils;
+const Cc = Components.classes;
+const Cr = Components.results;
+const Ci = Components.interfaces;
+
+Cu.import("resource://gre/modules/PageThumbs.jsm");
+Cu.import("resource://gre/modules/XPCOMUtils.jsm");
+
+XPCOMUtils.defineLazyModuleGetter(this, "Services",
+  "resource://gre/modules/Services.jsm");
+XPCOMUtils.defineLazyModuleGetter(this, "FileUtils",
+  "resource://gre/modules/FileUtils.jsm");
+
+/**
+ * Implements the thumbnail protocol handler responsible for moz-page-thumb: URIs.
+ */
+function Protocol() {
+}
+
+Protocol.prototype = {
+  /**
+   * The scheme used by this protocol.
+   */
+  get scheme() PageThumbs.scheme,
+
+  /**
+   * The default port for this protocol (we don't support ports).
+   */
+  get defaultPort() -1,
+
+  /**
+   * The flags specific to this protocol implementation.
+   */
+  get protocolFlags() {
+    return Ci.nsIProtocolHandler.URI_DANGEROUS_TO_LOAD |
+           Ci.nsIProtocolHandler.URI_NORELATIVE |
+           Ci.nsIProtocolHandler.URI_NOAUTH;
+  },
+
+  /**
+   * Creates a new URI object that is suitable for loading by this protocol.
+   * @param aSpec The URI string in UTF8 encoding.
+   * @param aOriginCharset The charset of the document from which the URI originated.
+   * @return The newly created URI.
+   */
+  newURI: function Proto_newURI(aSpec, aOriginCharset) {
+    let uri = Cc["@mozilla.org/network/simple-uri;1"].createInstance(Ci.nsIURI);
+    uri.spec = aSpec;
+    return uri;
+  },
+
+  /**
+   * Constructs a new channel from the given URI for this protocol handler.
+   * @param aURI The URI for which to construct a channel.
+   * @return The newly created channel.
+   */
+  newChannel: function Proto_newChannel(aURI) {
+    let {url} = parseURI(aURI);
+    let file = PageThumbsStorage.getFilePathForURL(url);
+    let fileuri = Services.io.newFileURI(new FileUtils.File(file));
+    return Services.io.newChannelFromURI(fileuri);
+  },
+
+  /**
+   * Decides whether to allow a blacklisted port.
+   * @return Always false, we'll never allow ports.
+   */
+  allowPort: function () false,
+
+  classID: Components.ID("{5a4ae9b5-f475-48ae-9dce-0b4c1d347884}"),
+  QueryInterface: XPCOMUtils.generateQI([Ci.nsIProtocolHandler])
+};
+
+this.NSGetFactory = XPCOMUtils.generateNSGetFactory([Protocol]);
+
+/**
+ * Parses a given URI and extracts all parameters relevant to this protocol.
+ * @param aURI The URI to parse.
+ * @return The parsed parameters.
+ */
+function parseURI(aURI) {
+  let {scheme, staticHost} = PageThumbs;
+  let re = new RegExp("^" + scheme + "://" + staticHost + ".*?\\?");
+  let query = aURI.spec.replace(re, "");
+  let params = {};
+
+  query.split("&").forEach(function (aParam) {
+    let [key, value] = aParam.split("=").map(decodeURIComponent);
+    params[key.toLowerCase()] = value;
+  });
+
+  return params;
+}