Bug 1298979 - Fix LegacyExtensionContext r=aswan

LegacyExtensionContext should inherit from BaseContext instead of
ExtensionContext, because the latter is moving to a separate process.

Remove the optional `url` parameter because the context is not a frame.
`url` is assigned to `sender.url`, which should only be set for frames.
The sender is only used in extension messaging when `runtime.connect` or
`runtime.sendMessage` are used (where `sender.url` is visible at the
receiver). Since legacy extensions don't send messages, there is no
point at all in setting the `url` value.

MozReview-Commit-ID: FJboNC2SZh0

--HG--
extra : rebase_source : bbfd6670355a3b9985b03b5a203f3b0a19cdfde4

browser/components/extensions/test/browser/browser_ext_legacy_extension_context_contentscript.js

@@ -104,7 +104,7 @@ add_task(function* test_legacy_extension_context_contentscript_connection() {
     });
   });
 
-  is(legacyContext.type, "legacy_extension",
+  is(legacyContext.envType, "legacy_extension",
      "LegacyExtensionContext instance has the expected type");
 
   ok(legacyContext.api, "Got the API object");

toolkit/components/extensions/Extension.jsm

@@ -4,7 +4,7 @@
 
 "use strict";
 
-this.EXPORTED_SYMBOLS = ["Extension", "ExtensionData", "ExtensionContext"];
+this.EXPORTED_SYMBOLS = ["Extension", "ExtensionData"];
 
 /* globals Extension ExtensionData */
 
@@ -272,6 +272,8 @@ let ProxyMessenger = {
     // Listen on the parent process message manager because `runtime.connect`
     // and `runtime.sendMessage` requests must be delivered to all frames in an
     // addon process (by the API contract).
+    // And legacy addons are not associated with a frame, so that is another
+    // reason for having a parent process manager here.
     let messageManagers = [Services.mm, pipmm];
 
     MessageChannel.addListener(messageManagers, "Extension:Connect", this);

toolkit/components/extensions/LegacyExtensionsUtils.jsm

@@ -17,43 +17,33 @@ const {classes: Cc, interfaces: Ci, utils: Cu, results: Cr} = Components;
 
 Cu.import("resource://gre/modules/XPCOMUtils.jsm");
 
-// Lazy imports.
 XPCOMUtils.defineLazyModuleGetter(this, "Extension",
                                   "resource://gre/modules/Extension.jsm");
-XPCOMUtils.defineLazyModuleGetter(this, "ExtensionContext",
-                                  "resource://gre/modules/Extension.jsm");
-XPCOMUtils.defineLazyModuleGetter(this, "NetUtil",
-                                  "resource://gre/modules/NetUtil.jsm");
 XPCOMUtils.defineLazyModuleGetter(this, "Services",
                                   "resource://gre/modules/Services.jsm");
 
+Cu.import("resource://gre/modules/ExtensionUtils.jsm");
+
+var {
+  BaseContext,
+  Messenger,
+} = ExtensionUtils;
+
 /**
  * Instances created from this class provide to a legacy extension
  * a simple API to exchange messages with a webextension.
  */
-var LegacyExtensionContext = class extends ExtensionContext {
+var LegacyExtensionContext = class extends BaseContext {
   /**
-   * Create a new LegacyExtensionContext given a target Extension instance and an optional
-   * url (which can be used to recognize the messages of container context).
+   * Create a new LegacyExtensionContext given a target Extension instance.
    *
    * @param {Extension} targetExtension
    *   The webextension instance associated with this context. This will be the
    *   instance of the newly created embedded webextension when this class is
    *   used through the EmbeddedWebExtensionsUtils.
-   * @param {Object} [optionalParams]
-   *   An object with the following properties:
-   * @param {string}  [optionalParams.url]
-   *   An URL to mark the messages sent from this context
-   *   (e.g. EmbeddedWebExtension sets it to the base url of the container addon).
    */
-  constructor(targetExtension, optionalParams = {}) {
-    let {url} = optionalParams;
-
-    super(targetExtension, {
-      contentWindow: null,
-      uri: NetUtil.newURI(url || "about:blank"),
-      type: "legacy_extension",
-    });
+  constructor(targetExtension) {
+    super("legacy_extension", targetExtension);
 
     // Legacy Extensions (xul overlays, bootstrap restartless and Addon SDK)
     // runs with a systemPrincipal.
@@ -70,6 +60,13 @@ var LegacyExtensionContext = class extends ExtensionContext {
       {value: cloneScope, enumerable: true, configurable: true, writable: true}
     );
 
+    let sender = {id: targetExtension.uuid};
+    let filter = {extensionId: targetExtension.id};
+    // Legacy addons live in the main process. Messages from other addons are
+    // Messages from WebExtensions are sent to the main process and forwarded via
+    // the parent process manager to the legacy extension.
+    this.messenger = new Messenger(this, [Services.cpmm], sender, filter);
+
     this.api = {
       browser: {
         runtime: {
@@ -92,13 +89,6 @@ var LegacyExtensionContext = class extends ExtensionContext {
     Cu.nukeSandbox(this.cloneScope);
     this.cloneScope = null;
   }
-
-  /**
-   * The LegacyExtensionContext is not a visible context.
-   */
-  get externallyVisible() {
-    return false;
-  }
 };
 
 var EmbeddedExtensionManager;
@@ -167,9 +157,7 @@ class EmbeddedExtension {
         // to subscribe its message listeners (which are supposed to be able to
         // receive any message that the embedded part can try to send to it
         // during its startup).
-        this.context = new LegacyExtensionContext(this.extension, {
-          url: this.resourceURI.resolve("/"),
-        });
+        this.context = new LegacyExtensionContext(this.extension);
 
         // Destroy the LegacyExtensionContext cloneScope when
         // the embedded webextensions is unloaded.

toolkit/components/extensions/test/xpcshell/test_ext_legacy_extension_context.js

@@ -18,7 +18,7 @@ const {LegacyExtensionContext} = Cu.import("resource://gre/modules/LegacyExtensi
  *    shutting down
  */
 add_task(function* test_legacy_extension_context() {
-  function backgroundScript() {
+  function background() {
     let bgURL = window.location.href;
 
     let extensionInfo = {
@@ -29,6 +29,8 @@ add_task(function* test_legacy_extension_context() {
 
     browser.test.sendMessage("webextension-ready", extensionInfo);
 
+    let port;
+
     browser.test.onMessage.addListener(msg => {
       if (msg == "do-send-message") {
         browser.runtime.sendMessage("webextension -> legacy_extension message").then(reply => {
@@ -37,19 +39,21 @@ add_task(function* test_legacy_extension_context() {
           browser.test.sendMessage("got-reply-message");
         });
       } else if (msg == "do-connect") {
-        let port = browser.runtime.connect();
+        port = browser.runtime.connect();
 
         port.onMessage.addListener(msg => {
           browser.test.assertEq("legacy_extension -> webextension port message", msg,
                                 "Got the expected message from the LegacyExtensionContext");
           port.postMessage("webextension -> legacy_extension port message");
         });
+      } else if (msg == "do-disconnect") {
+        port.disconnect();
       }
     });
   }
 
   let extensionData = {
-    background: "new " + backgroundScript,
+    background,
   };
 
   let extension = Extension.generate(extensionData);
@@ -65,15 +69,23 @@ add_task(function* test_legacy_extension_context() {
     });
   });
 
+  // Connect to the target extension as an external context
+  // using the given custom sender info.
+  let legacyContext;
+
+  extension.on("startup", function onStartup() {
+    extension.off("startup", onStartup);
+    legacyContext = new LegacyExtensionContext(extension);
+    extension.callOnClose({
+      close: () => legacyContext.unload(),
+    });
+  });
+
   yield extension.startup();
 
   let extensionInfo = yield waitForExtensionInfo;
 
-  // Connect to the target extension.id as an external context
-  // using the given custom sender info.
-  let legacyContext = new LegacyExtensionContext(extension);
-
-  equal(legacyContext.type, "legacy_extension",
+  equal(legacyContext.envType, "legacy_extension",
      "LegacyExtensionContext instance has the expected type");
 
   ok(legacyContext.api, "Got the expected API object");
@@ -146,11 +158,11 @@ add_task(function* test_legacy_extension_context() {
     port.onDisconnect.addListener(resolve);
   });
 
-  extension.shutdown();
+  extension.testMessage("do-disconnect");
 
   yield waitForDisconnect;
 
   do_print("Got the disconnect event on unload");
 
-  legacyContext.shutdown();
+  yield extension.shutdown();
 });