Bug 1591469, move reader mode to use JSWindowActor instead of message managers, r=Gijs

Differential Revision: https://phabricator.services.mozilla.com/D71452

browser/actors/AboutReaderChild.jsm

@@ -6,10 +6,6 @@
 
 var EXPORTED_SYMBOLS = ["AboutReaderChild"];
 
-const { ActorChild } = ChromeUtils.import(
-  "resource://gre/modules/ActorChild.jsm"
-);
-
 ChromeUtils.defineModuleGetter(
   this,
   "AboutReader",
@@ -26,25 +22,38 @@ ChromeUtils.defineModuleGetter(
   "resource://gre/modules/Readerable.jsm"
 );
 
-class AboutReaderChild extends ActorChild {
-  constructor(dispatcher) {
-    super(dispatcher);
+class AboutReaderChild extends JSWindowActorChild {
+  constructor() {
+    super();
 
+    this._reader = null;
     this._articlePromise = null;
     this._isLeavingReaderableReaderMode = false;
   }
 
+  willDestroy() {
+    this.cancelPotentialPendingReadabilityCheck();
+    this.readerModeHidden();
+  }
+
+  readerModeHidden() {
+    if (this._reader) {
+      this._reader.clearActor();
+    }
+    this._reader = null;
+  }
+
   receiveMessage(message) {
     switch (message.name) {
       case "Reader:ToggleReaderMode":
         if (!this.isAboutReader) {
-          this._articlePromise = ReaderMode.parseDocument(
-            this.content.document
-          ).catch(Cu.reportError);
-          ReaderMode.enterReaderMode(this.mm.docShell, this.content);
+          this._articlePromise = ReaderMode.parseDocument(this.document).catch(
+            Cu.reportError
+          );
+          ReaderMode.enterReaderMode(this.docShell, this.contentWindow);
         } else {
           this._isLeavingReaderableReaderMode = this.isReaderableAboutReader;
-          ReaderMode.leaveReaderMode(this.mm.docShell, this.content);
+          ReaderMode.leaveReaderMode(this.docShell, this.contentWindow);
         }
         break;
 
@@ -52,37 +61,40 @@ class AboutReaderChild extends ActorChild {
         this.updateReaderButton(!!(message.data && message.data.isArticle));
         break;
     }
+
+    // Forward the message to the reader if it has been created.
+    if (this._reader) {
+      this._reader.receiveMessage(message);
+    }
   }
 
   get isAboutReader() {
-    if (!this.content) {
+    if (!this.document) {
       return false;
     }
-    return this.content.document.documentURI.startsWith("about:reader");
+    return this.document.documentURI.startsWith("about:reader");
   }
 
   get isReaderableAboutReader() {
-    return (
-      this.isAboutReader &&
-      !this.content.document.documentElement.dataset.isError
-    );
+    return this.isAboutReader && !this.document.documentElement.dataset.isError;
   }
 
   handleEvent(aEvent) {
-    if (aEvent.originalTarget.defaultView != this.content) {
+    if (aEvent.originalTarget.defaultView != this.contentWindow) {
       return;
     }
 
     switch (aEvent.type) {
-      case "AboutReaderContentLoaded":
+      case "DOMContentLoaded":
         if (!this.isAboutReader) {
+          this.updateReaderButton();
           return;
         }
 
-        if (this.content.document.body) {
+        if (this.document.body) {
           // Update the toolbar icon to show the "reader active" icon.
-          this.mm.sendAsyncMessage("Reader:UpdateReaderButton");
-          new AboutReader(this.mm, this.content, this._articlePromise);
+          this.sendAsyncMessage("Reader:UpdateReaderButton");
+          this._reader = new AboutReader(this, this._articlePromise);
           this._articlePromise = null;
         }
         break;
@@ -92,7 +104,7 @@ class AboutReaderChild extends ActorChild {
         // this._isLeavingReaderableReaderMode is used here to keep the Reader Mode icon
         // visible in the location bar when transitioning from reader-mode page
         // back to the readable source page.
-        this.mm.sendAsyncMessage("Reader:UpdateReaderButton", {
+        this.sendAsyncMessage("Reader:UpdateReaderButton", {
           isArticle: this._isLeavingReaderableReaderMode,
         });
         if (this._isLeavingReaderableReaderMode) {
@@ -107,9 +119,6 @@ class AboutReaderChild extends ActorChild {
           this.updateReaderButton();
         }
         break;
-      case "DOMContentLoaded":
-        this.updateReaderButton();
-        break;
     }
   }
 
@@ -123,9 +132,9 @@ class AboutReaderChild extends ActorChild {
     if (
       !Readerable.isEnabledForParseOnLoad ||
       this.isAboutReader ||
-      !this.content ||
-      !(this.content.document instanceof this.content.HTMLDocument) ||
-      this.content.document.mozSyntheticDocument
+      !this.contentWindow ||
+      !(this.document instanceof this.contentWindow.HTMLDocument) ||
+      this.document.mozSyntheticDocument
     ) {
       return;
     }
@@ -135,11 +144,14 @@ class AboutReaderChild extends ActorChild {
 
   cancelPotentialPendingReadabilityCheck() {
     if (this._pendingReadabilityCheck) {
-      this.mm.removeEventListener(
-        "MozAfterPaint",
-        this._pendingReadabilityCheck
-      );
+      if (this._listenerWindow) {
+        this._listenerWindow.removeEventListener(
+          "MozAfterPaint",
+          this._pendingReadabilityCheck
+        );
+      }
       delete this._pendingReadabilityCheck;
+      delete this._listenerWindow;
     }
   }
 
@@ -153,28 +165,43 @@ class AboutReaderChild extends ActorChild {
       this,
       forceNonArticle
     );
-    this.mm.addEventListener("MozAfterPaint", this._pendingReadabilityCheck);
+
+    this._listenerWindow = this.contentWindow.windowRoot;
+    this.contentWindow.windowRoot.addEventListener(
+      "MozAfterPaint",
+      this._pendingReadabilityCheck
+    );
   }
 
   onPaintWhenWaitedFor(forceNonArticle, event) {
     // In non-e10s, we'll get called for paints other than ours, and so it's
     // possible that this page hasn't been laid out yet, in which case we
     // should wait until we get an event that does relate to our layout. We
-    // determine whether any of our this.content got painted by checking if there
-    // are any painted rects.
+    // determine whether any of our this.contentWindow got painted by checking
+    // if there are any painted rects.
     if (!event.clientRects.length) {
       return;
     }
 
     this.cancelPotentialPendingReadabilityCheck();
+
+    // Ignore errors from actors that have been unloaded before the
+    // paint event timer fires.
+    let document;
+    try {
+      document = this.document;
+    } catch (ex) {
+      return;
+    }
+
     // Only send updates when there are articles; there's no point updating with
     // |false| all the time.
-    if (Readerable.isProbablyReaderable(this.content.document)) {
-      this.mm.sendAsyncMessage("Reader:UpdateReaderButton", {
+    if (Readerable.isProbablyReaderable(document)) {
+      this.sendAsyncMessage("Reader:UpdateReaderButton", {
         isArticle: true,
       });
     } else if (forceNonArticle) {
-      this.mm.sendAsyncMessage("Reader:UpdateReaderButton", {
+      this.sendAsyncMessage("Reader:UpdateReaderButton", {
         isArticle: false,
       });
     }

browser/actors/AboutReaderParent.jsm

@@ -5,7 +5,7 @@
 
 "use strict";
 
-var EXPORTED_SYMBOLS = ["ReaderParent"];
+var EXPORTED_SYMBOLS = ["AboutReaderParent"];
 
 const { Services } = ChromeUtils.import("resource://gre/modules/Services.jsm");
 
@@ -24,61 +24,146 @@ const gStringBundle = Services.strings.createBundle(
   "chrome://global/locale/aboutReader.properties"
 );
 
-var ReaderParent = {
-  // Listeners are added in BrowserGlue.jsm
-  receiveMessage(message) {
+// A set of all of the AboutReaderParent actors that exist.
+// See bug 1631146 for a request for a less manual way of doing this.
+let gAllActors = new Set();
+
+// A map of message names to listeners that listen to messages
+// received by the AboutReaderParent actors.
+let gListeners = new Map();
+
+class AboutReaderParent extends JSWindowActorParent {
+  didDestroy() {
+    gAllActors.delete(this);
+  }
+
+  isReaderMode(browser) {
+    return browser.currentURI.spec.startsWith("about:reader");
+  }
+
+  static addMessageListener(name, listener) {
+    if (!gListeners.has(name)) {
+      gListeners.set(name, new Set([listener]));
+    } else {
+      gListeners.get(name).add(listener);
+    }
+  }
+
+  static removeMessageListener(name, listener) {
+    if (!gListeners.has(name)) {
+      return;
+    }
+
+    gListeners.get(name).delete(listener);
+  }
+
+  static broadcastAsyncMessage(name, data) {
+    for (let actor of gAllActors) {
+      // Ignore errors for actors that might not be valid yet or anymore.
+      try {
+        actor.sendAsyncMessage(name, data);
+      } catch (ex) {}
+    }
+  }
+
+  callListeners(message) {
+    let listeners = gListeners.get(message.name);
+    if (!listeners) {
+      return;
+    }
+
+    message.target = this.browsingContext.embedderElement;
+    for (let listener of listeners.values()) {
+      try {
+        listener.receiveMessage(message);
+      } catch (e) {
+        Cu.reportError(e);
+      }
+    }
+  }
+
+  async receiveMessage(message) {
     switch (message.name) {
       case "Reader:FaviconRequest": {
-        if (message.target.messageManager) {
-          try {
-            let preferredWidth = message.data.preferredWidth || 0;
-            let uri = Services.io.newURI(message.data.url);
+        try {
+          let preferredWidth = message.data.preferredWidth || 0;
+          let uri = Services.io.newURI(message.data.url);
+
+          let result = await new Promise(resolve => {
             PlacesUtils.favicons.getFaviconURLForPage(
               uri,
               iconUri => {
                 if (iconUri) {
                   iconUri = PlacesUtils.favicons.getFaviconLinkForIcon(iconUri);
-                  message.target.messageManager.sendAsyncMessage(
-                    "Reader:FaviconReturn",
-                    {
-                      url: message.data.url,
-                      faviconUrl: iconUri.pathQueryRef.replace(/^favicon:/, ""),
-                    }
-                  );
+                  resolve({
+                    url: message.data.url,
+                    faviconUrl: iconUri.pathQueryRef.replace(/^favicon:/, ""),
+                  });
+                } else {
+                  resolve(null);
                 }
               },
               preferredWidth
             );
-          } catch (ex) {
-            Cu.reportError(
-              "Error requesting favicon URL for about:reader content: " + ex
-            );
-          }
+          });
+
+          this.callListeners(message);
+          return result;
+        } catch (ex) {
+          Cu.reportError(
+            "Error requesting favicon URL for about:reader content: " + ex
+          );
         }
+
         break;
       }
 
       case "Reader:UpdateReaderButton": {
-        let browser = message.target;
+        let browser = this.browsingContext.embedderElement;
+        if (!browser) {
+          return undefined;
+        }
+
+        if (browser.outerBrowser) {
+          browser = browser.outerBrowser; // handle RDM mode
+        }
+
         if (message.data && message.data.isArticle !== undefined) {
           browser.isArticle = message.data.isArticle;
         }
         this.updateReaderButton(browser);
+        this.callListeners(message);
         break;
       }
+
+      default:
+        this.callListeners(message);
+        break;
     }
-  },
+
+    return undefined;
+  }
+
+  static updateReaderButton(browser) {
+    let windowGlobal = browser.browsingContext.currentWindowGlobal;
+    let actor = windowGlobal.getActor("AboutReader");
+    actor.updateReaderButton(browser);
+  }
 
   updateReaderButton(browser) {
-    let win = browser.ownerGlobal;
-    if (browser != win.gBrowser.selectedBrowser) {
+    let tabBrowser = browser.getTabBrowser();
+    if (!tabBrowser || browser != tabBrowser.selectedBrowser) {
       return;
     }
 
+    let win = browser.ownerGlobal;
+
     let button = win.document.getElementById("reader-mode-button");
     let menuitem = win.document.getElementById("menu_readerModeItem");
     let key = win.document.getElementById("key_toggleReaderMode");
-    if (browser.currentURI.spec.startsWith("about:reader")) {
+    if (this.isReaderMode(browser)) {
+      gAllActors.add(this);
+
       let closeText = gStringBundle.GetStringFromName("readerView.close");
 
       button.setAttribute("readeractive", true);
@@ -115,25 +200,35 @@ var ReaderParent = {
         Services.obs.notifyObservers(null, "reader-mode-available");
       }
     }
-  },
+  }
 
-  forceShowReaderIcon(browser) {
+  static forceShowReaderIcon(browser) {
     browser.isArticle = true;
-    this.updateReaderButton(browser);
-  },
+    AboutReaderParent.updateReaderButton(browser);
+  }
 
-  buttonClick(event) {
+  static buttonClick(event) {
     if (event.button != 0) {
       return;
     }
-    this.toggleReaderMode(event);
-  },
+    AboutReaderParent.toggleReaderMode(event);
+  }
 
-  toggleReaderMode(event) {
+  static toggleReaderMode(event) {
     let win = event.target.ownerGlobal;
-    let browser = win.gBrowser.selectedBrowser;
-    browser.messageManager.sendAsyncMessage("Reader:ToggleReaderMode");
-  },
+    if (win.gBrowser) {
+      let browser = win.gBrowser.selectedBrowser;
+
+      let windowGlobal = browser.browsingContext.currentWindowGlobal;
+      let actor = windowGlobal.getActor("AboutReader");
+      if (actor) {
+        if (actor.isReaderMode(browser)) {
+          gAllActors.delete(this);
+        }
+        actor.sendAsyncMessage("Reader:ToggleReaderMode", {});
+      }
+    }
+  }
 
   /**
    * Gets an article for a given URL. This method will download and parse a document.
@@ -152,5 +247,5 @@ var ReaderParent = {
       Cu.reportError("Error downloading and parsing document: " + e);
       return null;
     });
-  },
-};
+  }
+}

browser/actors/moz.build

@@ -10,6 +10,9 @@ with Files("**"):
 with Files("ContentSearch*.jsm"):
     BUG_COMPONENT = ("Firefox", "Search")
 
+with Files("AboutReaderParent.jsm"):
+    BUG_COMPONENT = ("Toolkit", "Reader Mode")
+
 with Files("LightweightThemeChild.jsm"):
     BUG_COMPONENT = ("WebExtensions", "Themes")
 
@@ -34,6 +37,7 @@ FINAL_TARGET_FILES.actors += [
     'AboutProtectionsChild.jsm',
     'AboutProtectionsParent.jsm',
     'AboutReaderChild.jsm',
+    'AboutReaderParent.jsm',
     'AboutTabCrashedChild.jsm',
     'AboutTabCrashedParent.jsm',
     'BlockedSiteChild.jsm',

browser/base/content/browser-fullZoom.js

@@ -334,7 +334,7 @@ var FullZoom = {
   async reduce() {
     let browser = gBrowser.selectedBrowser;
     if (browser.currentURI.spec.startsWith("about:reader")) {
-      browser.messageManager.sendAsyncMessage("Reader:ZoomOut");
+      browser.sendMessageToActor("Reader:ZoomOut", {}, "AboutReader");
     } else if (this._isPDFViewer(browser)) {
       browser.messageManager.sendAsyncMessage("PDFJS:ZoomOut");
     } else {
@@ -351,7 +351,7 @@ var FullZoom = {
   async enlarge() {
     let browser = gBrowser.selectedBrowser;
     if (browser.currentURI.spec.startsWith("about:reader")) {
-      browser.messageManager.sendAsyncMessage("Reader:ZoomIn");
+      browser.sendMessageToActor("Reader:ZoomIn", {}, "AboutReader");
     } else if (this._isPDFViewer(browser)) {
       browser.messageManager.sendAsyncMessage("PDFJS:ZoomIn");
     } else {
@@ -371,7 +371,7 @@ var FullZoom = {
   changeZoomBy(aBrowser, aValue) {
     if (aBrowser.currentURI.spec.startsWith("about:reader")) {
       const message = aValue > 0 ? "Reader::ZoomIn" : "Reader:ZoomOut";
-      aBrowser.messageManager.sendAsyncMessage(message);
+      aBrowser.sendMessageToActor(message, {}, "AboutReader");
       return;
     } else if (this._isPDFViewer(aBrowser)) {
       const message = aValue > 0 ? "PDFJS::ZoomIn" : "PDFJS:ZoomOut";
@@ -412,7 +412,7 @@ var FullZoom = {
   reset: function FullZoom_reset(browser = gBrowser.selectedBrowser) {
     let forceValue;
     if (browser.currentURI.spec.startsWith("about:reader")) {
-      browser.messageManager.sendAsyncMessage("Reader:ResetZoom");
+      browser.sendMessageToActor("Reader:ResetZoom", {}, "AboutReader");
     } else if (this._isPDFViewer(browser)) {
       browser.messageManager.sendAsyncMessage("PDFJS:ZoomReset");
       // Ensure that the UI elements of the PDF viewer won't be zoomed in/out

browser/base/content/browser-sets.inc

@@ -42,7 +42,7 @@
     <command id="View:PageSource" oncommand="BrowserViewSource(window.gBrowser.selectedBrowser);"/>
     <command id="View:PageInfo" oncommand="BrowserPageInfo();"/>
     <command id="View:FullScreen" oncommand="BrowserFullScreen();"/>
-    <command id="View:ReaderView" oncommand="ReaderParent.toggleReaderMode(event);"/>
+    <command id="View:ReaderView" oncommand="AboutReaderParent.toggleReaderMode(event);"/>
     <command id="View:PictureInPicture" oncommand="PictureInPicture.onCommand(event);"/>
     <command id="cmd_find" oncommand="gLazyFindCommand('onFindCommand')"/>
     <command id="cmd_findAgain" oncommand="gLazyFindCommand('onFindAgainCommand', false)"/>

browser/base/content/browser.js

@@ -16,6 +16,7 @@ ChromeUtils.import("resource://gre/modules/NotificationDB.jsm");
 
 XPCOMUtils.defineLazyModuleGetters(this, {
   AboutNewTab: "resource:///modules/AboutNewTab.jsm",
+  AboutReaderParent: "resource:///actors/AboutReaderParent.jsm",
   AddonManager: "resource://gre/modules/AddonManager.jsm",
   AMTelemetry: "resource://gre/modules/AddonManager.jsm",
   NewTabPagePreloading: "resource:///modules/NewTabPagePreloading.jsm",
@@ -60,7 +61,6 @@ XPCOMUtils.defineLazyModuleGetters(this, {
   PromiseUtils: "resource://gre/modules/PromiseUtils.jsm",
   // TODO (Bug 1529552): Remove once old urlbar code goes away.
   ReaderMode: "resource://gre/modules/ReaderMode.jsm",
-  ReaderParent: "resource:///modules/ReaderParent.jsm",
   RFPHelper: "resource://gre/modules/RFPHelper.jsm",
   SafeBrowsing: "resource://gre/modules/SafeBrowsing.jsm",
   Sanitizer: "resource:///modules/Sanitizer.jsm",
@@ -5283,7 +5283,7 @@ var XULBrowserWindow = {
     }
     Services.obs.notifyObservers(null, "touchbar-location-change", location);
     UpdateBackForwardCommands(gBrowser.webNavigation);
-    ReaderParent.updateReaderButton(gBrowser.selectedBrowser);
+    AboutReaderParent.updateReaderButton(gBrowser.selectedBrowser);
 
     if (!gMultiProcessBrowser) {
       // Bug 1108553 - Cannot rotate images with e10s
@@ -5886,9 +5886,13 @@ var TabsProgressListener = {
     if (aFlags & Ci.nsIWebProgressListener.LOCATION_CHANGE_SAME_DOCUMENT) {
       // Reader mode cares about history.pushState and friends.
       // FIXME: The content process should manage this directly (bug 1445351).
-      aBrowser.messageManager.sendAsyncMessage("Reader:PushState", {
-        isArticle: aBrowser.isArticle,
-      });
+      aBrowser.sendMessageToActor(
+        "Reader:PushState",
+        {
+          isArticle: aBrowser.isArticle,
+        },
+        "AboutReader"
+      );
       return;
     }
 

browser/base/content/browser.xhtml

@@ -1027,7 +1027,7 @@
                        tooltip="dynamic-shortcut-tooltip"
                        role="button"
                        hidden="true"
-                       onclick="ReaderParent.buttonClick(event);"/>
+                       onclick="AboutReaderParent.buttonClick(event);"/>
                 <toolbarbutton id="urlbar-zoom-button"
                        onclick="FullZoom.reset();"
                        tooltip="dynamic-shortcut-tooltip"

browser/base/content/test/performance/browser_startup_content.js

@@ -45,7 +45,6 @@ const whitelist = {
     "resource:///actors/SearchTelemetryChild.jsm",
     "resource:///actors/PromptChild.jsm",
     "resource://gre/actors/AutoCompleteChild.jsm",
-    "resource://gre/modules/ActorChild.jsm",
     "resource://gre/modules/ActorManagerChild.jsm",
     "resource://gre/modules/E10SUtils.jsm",
     "resource://gre/modules/Readerable.jsm",

browser/components/BrowserGlue.jsm

@@ -157,6 +157,21 @@ let ACTORS = {
     matches: ["about:protections"],
   },
 
+  AboutReader: {
+    parent: {
+      moduleURI: "resource:///actors/AboutReaderParent.jsm",
+    },
+    child: {
+      moduleURI: "resource:///actors/AboutReaderChild.jsm",
+      events: {
+        DOMContentLoaded: {},
+        pageshow: { mozSystemGroup: true },
+        pagehide: { mozSystemGroup: true },
+      },
+    },
+    messageManagerGroups: ["browsers"],
+  },
+
   AboutTabCrashed: {
     parent: {
       moduleURI: "resource:///actors/AboutTabCrashedParent.jsm",
@@ -521,20 +536,6 @@ let ACTORS = {
 };
 
 let LEGACY_ACTORS = {
-  AboutReader: {
-    child: {
-      module: "resource:///actors/AboutReaderChild.jsm",
-      group: "browsers",
-      events: {
-        AboutReaderContentLoaded: { wantUntrusted: true },
-        DOMContentLoaded: {},
-        pageshow: { mozSystemGroup: true },
-        pagehide: { mozSystemGroup: true },
-      },
-      messages: ["Reader:ToggleReaderMode", "Reader:PushState"],
-    },
-  },
-
   URIFixup: {
     child: {
       module: "resource:///actors/URIFixupChild.jsm",
@@ -700,7 +701,6 @@ XPCOMUtils.defineLazyModuleGetters(this, {
   AboutLoginsParent: "resource:///modules/AboutLoginsParent.jsm",
   AsyncPrefs: "resource://gre/modules/AsyncPrefs.jsm",
   PluginManager: "resource:///actors/PluginParent.jsm",
-  ReaderParent: "resource:///modules/ReaderParent.jsm",
 });
 
 /**

browser/components/extensions/parent/ext-browser.js

@@ -25,6 +25,11 @@ ChromeUtils.defineModuleGetter(
   "PromiseUtils",
   "resource://gre/modules/PromiseUtils.jsm"
 );
+ChromeUtils.defineModuleGetter(
+  this,
+  "AboutReaderParent",
+  "resource:///actors/AboutReaderParent.jsm"
+);
 
 var { ExtensionError } = ExtensionUtils;
 
@@ -352,7 +357,7 @@ class TabTracker extends TabTrackerBase {
     windowTracker.addOpenListener(this._handleWindowOpen);
     windowTracker.addCloseListener(this._handleWindowClose);
 
-    Services.mm.addMessageListener("Reader:UpdateReaderButton", this);
+    AboutReaderParent.addMessageListener("Reader:UpdateReaderButton", this);
 
     /* eslint-disable mozilla/balanced-listeners */
     this.on("tab-detached", this._handleTabDestroyed);

browser/components/extensions/parent/ext-tabs.js

@@ -1489,8 +1489,11 @@ this.tabs = class extends ExtensionAPI {
             );
           }
           let nativeTab = getTabOrActive(tabId);
-          nativeTab.linkedBrowser.messageManager.sendAsyncMessage(
-            "Reader:ToggleReaderMode"
+
+          nativeTab.linkedBrowser.sendMessageToActor(
+            "Reader:ToggleReaderMode",
+            {},
+            "AboutReader"
           );
         },
 

browser/components/newtab/lib/ASRouterTriggerListeners.jsm

@@ -11,6 +11,7 @@ const { XPCOMUtils } = ChromeUtils.import(
 XPCOMUtils.defineLazyModuleGetters(this, {
   PrivateBrowsingUtils: "resource://gre/modules/PrivateBrowsingUtils.jsm",
   EveryWindow: "resource:///modules/EveryWindow.jsm",
+  AboutReaderParent: "resource:///actors/AboutReaderParent.jsm",
 });
 
 const FEW_MINUTES = 15 * 60 * 1000; // 15 mins
@@ -99,7 +100,7 @@ this.ASRouterTriggerListeners = new Map([
       init(triggerHandler, hosts, patterns) {
         if (!this._initialized) {
           this.receiveMessage = this.receiveMessage.bind(this);
-          Services.mm.addMessageListener(this.readerModeEvent, this);
+          AboutReaderParent.addMessageListener(this.readerModeEvent, this);
           this._triggerHandler = triggerHandler;
           this._initialized = true;
         }
@@ -128,7 +129,7 @@ this.ASRouterTriggerListeners = new Map([
 
       uninit() {
         if (this._initialized) {
-          Services.mm.removeMessageListener(this.readerModeEvent, this);
+          AboutReaderParent.removeMessageListener(this.readerModeEvent, this);
           this._initialized = false;
           this._triggerHandler = null;
           this._hosts = new Set();

browser/components/newtab/test/browser/browser_asrouter_trigger_listeners.js

@@ -63,7 +63,10 @@ add_task(async function check_openArticleURL() {
   // Send a message from the content page (the TEST_URL) to the parent
   // This should trigger the `receiveMessage` cb in the articleTrigger
   await ContentTask.spawn(win.gBrowser.selectedBrowser, null, async () => {
-    sendAsyncMessage("Reader:UpdateReaderButton", { isArticle: true });
+    let readerActor = content.windowGlobalChild.getActor("AboutReader");
+    readerActor.sendAsyncMessage("Reader:UpdateReaderButton", {
+      isArticle: true,
+    });
   });
 
   await listenerTriggered.then(data =>

browser/components/pocket/content/SaveToPocket.jsm

@@ -29,6 +29,11 @@ ChromeUtils.defineModuleGetter(
   "ReaderMode",
   "resource://gre/modules/ReaderMode.jsm"
 );
+ChromeUtils.defineModuleGetter(
+  this,
+  "AboutReaderParent",
+  "resource:///actors/AboutReaderParent.jsm"
+);
 
 var EXPORTED_SYMBOLS = ["SaveToPocket"];
 
@@ -244,8 +249,8 @@ var SaveToPocket = {
       this.updateElements(false);
       Services.obs.addObserver(this, "browser-delayed-startup-finished");
     }
-    Services.mm.addMessageListener("Reader:OnSetup", this);
-    Services.mm.addMessageListener("Reader:Clicked-pocket-button", this);
+    AboutReaderParent.addMessageListener("Reader:OnSetup", this);
+    AboutReaderParent.addMessageListener("Reader:Clicked-pocket-button", this);
   },
 
   observe(subject, topic, data) {
@@ -265,7 +270,7 @@ var SaveToPocket = {
 
   onPrefChange(pref, oldValue, newValue) {
     if (!newValue) {
-      Services.mm.broadcastAsyncMessage("Reader:RemoveButton", {
+      AboutReaderParent.broadcastAsyncMessage("Reader:RemoveButton", {
         id: "pocket-button",
       });
       PocketOverlay.shutdown();
@@ -277,7 +282,7 @@ var SaveToPocket = {
       // If we don't have this, there's also no possibility of there being a reader
       // mode tab already loaded. We'll get an Reader:OnSetup message when that happens.
       if (this._readerButtonData.title) {
-        Services.mm.broadcastAsyncMessage(
+        AboutReaderParent.broadcastAsyncMessage(
           "Reader:AddButton",
           this._readerButtonData
         );
@@ -319,9 +324,10 @@ var SaveToPocket = {
           this._readerButtonData.title = button.getAttribute("tooltiptext");
         }
         // Tell the reader about our button.
-        message.target.messageManager.sendAsyncMessage(
+        message.target.sendMessageToActor(
           "Reader:AddButton",
-          this._readerButtonData
+          this._readerButtonData,
+          "AboutReader"
         );
         break;
       }

browser/components/uitour/UITour.jsm

@@ -46,8 +46,8 @@ ChromeUtils.defineModuleGetter(
 );
 ChromeUtils.defineModuleGetter(
   this,
-  "ReaderParent",
-  "resource:///modules/ReaderParent.jsm"
+  "AboutReaderParent",
+  "resource:///actors/AboutReaderParent.jsm"
 );
 ChromeUtils.defineModuleGetter(
   this,
@@ -662,14 +662,14 @@ var UITour = {
       }
 
       case "forceShowReaderIcon": {
-        ReaderParent.forceShowReaderIcon(browser);
+        AboutReaderParent.forceShowReaderIcon(browser);
         break;
       }
 
       case "toggleReaderMode": {
         let targetPromise = this.getTarget(window, "readerMode-urlBar");
         targetPromise.then(target => {
-          ReaderParent.toggleReaderMode({ target: target.node });
+          AboutReaderParent.toggleReaderMode({ target: target.node });
         });
         break;
       }

browser/modules/moz.build

@@ -79,9 +79,6 @@ with Files("PermissionUI.jsm"):
 with Files("ProcessHangMonitor.jsm"):
     BUG_COMPONENT = ("Core", "DOM: Content Processes")
 
-with Files("ReaderParent.jsm"):
-    BUG_COMPONENT = ("Toolkit", "Reader Mode")
-
 with Files("Sanitizer.jsm"):
     BUG_COMPONENT = ("Firefox", "Preferences")
 
@@ -145,7 +142,6 @@ EXTRA_JS_MODULES += [
     'PermissionUI.jsm',
     'PingCentre.jsm',
     'ProcessHangMonitor.jsm',
-    'ReaderParent.jsm',
     'Sanitizer.jsm',
     'SelectionChangedMenulist.jsm',
     'SiteDataManager.jsm',

toolkit/components/narrate/NarrateControls.jsm

@@ -21,8 +21,7 @@ var gStrings = Services.strings.createBundle(
   "chrome://global/locale/narrate.properties"
 );
 
-function NarrateControls(mm, win, languagePromise) {
-  this._mm = mm;
+function NarrateControls(win, languagePromise) {
   this._winRef = Cu.getWeakReference(win);
   this._languagePromise = languagePromise;
 

toolkit/components/reader/AboutReader.jsm

@@ -47,7 +47,8 @@ const zoomOnMeta =
 const gIsFirefoxDesktop =
   Services.appinfo.ID == "{ec8030f7-c20a-464f-9b0e-13a3a9e97384}";
 
-var AboutReader = function(mm, win, articlePromise) {
+var AboutReader = function(actor, articlePromise) {
+  let win = actor.contentWindow;
   let url = this._getOriginalUrl(win);
   if (!(url.startsWith("http://") || url.startsWith("https://"))) {
     let errorMsg =
@@ -62,14 +63,7 @@ var AboutReader = function(mm, win, articlePromise) {
 
   let doc = win.document;
 
-  this._mm = mm;
-  this._mm.addMessageListener("Reader:CloseDropdown", this);
-  this._mm.addMessageListener("Reader:AddButton", this);
-  this._mm.addMessageListener("Reader:RemoveButton", this);
-  this._mm.addMessageListener("Reader:GetStoredArticleData", this);
-  this._mm.addMessageListener("Reader:ZoomIn", this);
-  this._mm.addMessageListener("Reader:ZoomOut", this);
-  this._mm.addMessageListener("Reader:ResetZoom", this);
+  this._actor = actor;
 
   this._docRef = Cu.getWeakReference(doc);
   this._winRef = Cu.getWeakReference(win);
@@ -136,7 +130,7 @@ var AboutReader = function(mm, win, articlePromise) {
 
   if (gIsFirefoxDesktop) {
     // we're ready for any external setup, send a signal for that.
-    this._mm.sendAsyncMessage("Reader:OnSetup");
+    this._actor.sendAsyncMessage("Reader:OnSetup");
   }
 
   let colorSchemeValues = JSON.parse(
@@ -193,7 +187,7 @@ var AboutReader = function(mm, win, articlePromise) {
   this._setupLineHeightButtons();
 
   if (win.speechSynthesis && Services.prefs.getBoolPref("narrate.enabled")) {
-    new NarrateControls(mm, win, this._languagePromise);
+    new NarrateControls(win, this._languagePromise);
   }
 
   this._loadArticle();
@@ -292,26 +286,8 @@ AboutReader.prototype = {
     ));
   },
 
-  // Provides unique view Id.
-  get viewId() {
-    let _viewId = Cc["@mozilla.org/uuid-generator;1"]
-      .getService(Ci.nsIUUIDGenerator)
-      .generateUUID()
-      .toString();
-    Object.defineProperty(this, "viewId", { value: _viewId });
-
-    return _viewId;
-  },
-
   receiveMessage(message) {
     switch (message.name) {
-      // Triggered by Android user pressing BACK while the banner font-dropdown is open.
-      case "Reader:CloseDropdown": {
-        // Just close it.
-        this._closeDropdowns();
-        break;
-      }
-
       case "Reader:AddButton": {
         if (
           message.data.id &&
@@ -334,7 +310,7 @@ AboutReader.prototype = {
           let tb = this._toolbarElement;
           tb.appendChild(btn);
           this._setupButton(message.data.id, button => {
-            this._mm.sendAsyncMessage(
+            this._actor.sendAsyncMessage(
               "Reader:Clicked-" + button.dataset.buttonid,
               { article: this._article }
             );
@@ -351,12 +327,6 @@ AboutReader.prototype = {
         }
         break;
       }
-      case "Reader:GetStoredArticleData": {
-        this._mm.sendAsyncMessage("Reader:StoredArticleData", {
-          article: this._article,
-        });
-        break;
-      }
       case "Reader:ZoomIn": {
         this._changeFontSize(+1);
         break;
@@ -405,7 +375,6 @@ AboutReader.prototype = {
           }
 
           let isScrollingUp = this._scrollOffset > vv.pageTop;
-          this._setSystemUIVisibility(isScrollingUp);
           this._setToolbarVisibility(isScrollingUp);
         }
 
@@ -464,35 +433,18 @@ AboutReader.prototype = {
         // Close the Banners Font-dropdown, cleanup Android BackPressListener.
         this._closeDropdowns();
 
-        this._mm.removeMessageListener("Reader:CloseDropdown", this);
-        this._mm.removeMessageListener("Reader:AddButton", this);
-        this._mm.removeMessageListener("Reader:RemoveButton", this);
-        this._mm.removeMessageListener("Reader:GetStoredArticleData", this);
-        this._mm.removeMessageListener("Reader:ZoomIn", this);
-        this._mm.removeMessageListener("Reader:ZoomOut", this);
-        this._mm.removeMessageListener("Reader:ResetZoom", this);
-        this._windowUnloaded = true;
+        this._actor.readerModeHidden();
+        this.clearActor();
         break;
     }
   },
 
-  observe(subject, topic, data) {
-    if (
-      subject.QueryInterface(Ci.nsISupportsPRUint64).data != this._innerWindowId
-    ) {
-      return;
-    }
-
-    Services.obs.removeObserver(this, "inner-window-destroyed");
-
-    this._mm.removeMessageListener("Reader:CloseDropdown", this);
-    this._mm.removeMessageListener("Reader:AddButton", this);
-    this._mm.removeMessageListener("Reader:RemoveButton", this);
-    this._windowUnloaded = true;
+  clearActor() {
+    this._actor = null;
   },
 
   _onReaderClose() {
-    ReaderMode.leaveReaderMode(this._mm.docShell, this._win);
+    ReaderMode.leaveReaderMode(this._actor.docShell, this._win);
   },
 
   async _resetFontSize() {
@@ -858,10 +810,6 @@ AboutReader.prototype = {
     AsyncPrefs.set("reader.font_type", this._fontType);
   },
 
-  _setSystemUIVisibility(visible) {
-    this._mm.sendAsyncMessage("Reader:SystemUIVisibility", { visible });
-  },
-
   _setToolbarVisibility(visible) {
     let tb = this._toolbarElement;
 
@@ -893,7 +841,7 @@ AboutReader.prototype = {
       article = await this._articlePromise;
     } else {
       try {
-        article = await this._getArticle(url);
+        article = await ReaderMode.downloadAndParseDocument(url);
       } catch (e) {
         if (e && e.newURL) {
           let readerURL = "about:reader?url=" + encodeURIComponent(e.newURL);
@@ -903,7 +851,7 @@ AboutReader.prototype = {
       }
     }
 
-    if (this._windowUnloaded) {
+    if (!this._actor) {
       return;
     }
 
@@ -918,38 +866,15 @@ AboutReader.prototype = {
     this._showContent(article);
   },
 
-  _getArticle(url) {
-    if (this.PLATFORM_HAS_CACHE) {
-      return new Promise((resolve, reject) => {
-        let listener = message => {
-          this._mm.removeMessageListener("Reader:ArticleData", listener);
-          if (message.data.newURL) {
-            reject({ newURL: message.data.newURL });
-            return;
-          }
-          resolve(message.data.article);
-        };
-        this._mm.addMessageListener("Reader:ArticleData", listener);
-        this._mm.sendAsyncMessage("Reader:ArticleGet", { url });
-      });
-    }
-    return ReaderMode.downloadAndParseDocument(url);
-  },
-
-  _requestFavicon() {
-    let handleFaviconReturn = message => {
-      this._mm.removeMessageListener(
-        "Reader:FaviconReturn",
-        handleFaviconReturn
-      );
-      this._loadFavicon(message.data.url, message.data.faviconUrl);
-    };
-
-    this._mm.addMessageListener("Reader:FaviconReturn", handleFaviconReturn);
-    this._mm.sendAsyncMessage("Reader:FaviconRequest", {
+  async _requestFavicon() {
+    let iconDetails = await this._actor.sendQuery("Reader:FaviconRequest", {
       url: this._article.url,
       preferredWidth: 16 * this._win.devicePixelRatio,
     });
+
+    if (iconDetails) {
+      this._loadFavicon(iconDetails.url, iconDetails.faviconUrl);
+    }
   },
 
   _loadFavicon(url, faviconUrl) {
@@ -1134,7 +1059,7 @@ AboutReader.prototype = {
       // No need to show progress if the article has been loaded,
       // if the window has been unloaded, or if there was an error
       // trying to load the article.
-      if (this._article || this._windowUnloaded || this._error) {
+      if (this._article || !this._actor || this._error) {
         return;
       }
 
@@ -1300,7 +1225,6 @@ AboutReader.prototype = {
 
     // Trigger BackPressListener initialization in Android.
     dropdown.classList.add("open");
-    this._mm.sendAsyncMessage("Reader:DropdownOpened", this.viewId);
   },
 
   /*
@@ -1318,11 +1242,6 @@ AboutReader.prototype = {
     for (let dropdown of openDropdowns) {
       dropdown.classList.remove("open");
     }
-
-    // Trigger BackPressListener cleanup in Android.
-    if (openDropdowns.length) {
-      this._mm.sendAsyncMessage("Reader:DropdownClosed", this.viewId);
-    }
   },
 
   /*

toolkit/components/reader/content/aboutReader.html

@@ -10,7 +10,6 @@
   <meta content="text/html; charset=UTF-8" http-equiv="content-type" />
   <meta name="viewport" content="width=device-width; user-scalable=0" />
   <link rel="stylesheet" href="chrome://global/skin/aboutReader.css" type="text/css"/>
-  <script src="chrome://global/content/reader/aboutReader.js"></script>
 </head>
 
 <body>

toolkit/components/reader/content/aboutReader.js

@@ -1,11 +0,0 @@
-/* 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";
-
-window.addEventListener("DOMContentLoaded", function() {
-  document.dispatchEvent(
-    new CustomEvent("AboutReaderContentLoaded", { bubbles: true })
-  );
-});

toolkit/components/reader/jar.mn

@@ -4,4 +4,3 @@
 
 toolkit.jar:
   content/global/reader/aboutReader.html             (content/aboutReader.html)
-  content/global/reader/aboutReader.js               (content/aboutReader.js)

toolkit/components/reader/test/browser.ini

@@ -8,6 +8,10 @@ support-files =
 [browser_readerMode_hidden_nodes.js]
 support-files =
   readerModeArticleHiddenNodes.html
+[browser_readerMode_pocket.js]
+support-files =
+  readerModeArticleShort.html
+  readerModeArticleMedium.html
 [browser_readerMode_with_anchor.js]
 skip-if = fission # Bug 1616805
 support-files =

toolkit/components/reader/test/browser_readerMode_pocket.js

@@ -0,0 +1,90 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/ */
+"use strict";
+
+// This test verifies that the Save To Pocket button appears in reader mode,
+// and is toggled hidden and visible when pocket is disabled and enabled.
+
+const TEST_PATH = getRootDirectory(gTestPath).replace(
+  "chrome://mochitests/content",
+  "http://example.com"
+);
+
+async function getPocketButtonsCount(browser) {
+  return SpecialPowers.spawn(browser, [], () => {
+    return content.document.getElementsByClassName("pocket-button").length;
+  });
+}
+
+add_task(async function() {
+  // set the pocket preference before beginning.
+  await SpecialPowers.pushPrefEnv({
+    set: [["extensions.pocket.enabled", true]],
+  });
+
+  var readerButton = document.getElementById("reader-mode-button");
+
+  let tab1 = await BrowserTestUtils.openNewForegroundTab(
+    gBrowser,
+    TEST_PATH + "readerModeArticleShort.html"
+  );
+
+  let promiseTabLoad = promiseTabLoadEvent(tab1);
+  readerButton.click();
+  await promiseTabLoad;
+
+  let tab2 = await BrowserTestUtils.openNewForegroundTab(
+    gBrowser,
+    TEST_PATH + "readerModeArticleMedium.html"
+  );
+
+  promiseTabLoad = promiseTabLoadEvent(tab2);
+  readerButton.click();
+  await promiseTabLoad;
+
+  is(
+    await getPocketButtonsCount(tab1.linkedBrowser),
+    1,
+    "tab 1 has a pocket button"
+  );
+  is(
+    await getPocketButtonsCount(tab1.linkedBrowser),
+    1,
+    "tab 2 has a pocket button"
+  );
+
+  // Turn off the pocket preference. The Save To Pocket buttons should disappear.
+  await SpecialPowers.pushPrefEnv({
+    set: [["extensions.pocket.enabled", false]],
+  });
+
+  is(
+    await getPocketButtonsCount(tab1.linkedBrowser),
+    0,
+    "tab 1 has no pocket button"
+  );
+  is(
+    await getPocketButtonsCount(tab1.linkedBrowser),
+    0,
+    "tab 2 has no pocket button"
+  );
+
+  // Turn on the pocket preference. The Save To Pocket buttons should reappear again.
+  await SpecialPowers.pushPrefEnv({
+    set: [["extensions.pocket.enabled", true]],
+  });
+
+  is(
+    await getPocketButtonsCount(tab1.linkedBrowser),
+    1,
+    "tab 1 has a pocket button again"
+  );
+  is(
+    await getPocketButtonsCount(tab1.linkedBrowser),
+    1,
+    "tab 2 has a pocket button again"
+  );
+
+  BrowserTestUtils.removeTab(tab1);
+  BrowserTestUtils.removeTab(tab2);
+});