Bug 1458327 - 2. Let ModuleManager manage more aspects of modules; r=esawin

Let ModuleManager keep the current settings and enabled states for
modules. It initializes settings and module states from the window
init-data, and then listens to changes in them.

Having ModuleManager manage these states helps keeping things
consistent, and makes it possible for future optimizations like
delay-loading modules.

MozReview-Commit-ID: AM6lAxnUGhd

--HG--
extra : rebase_source : 2751990bec6054cc36104957690d8fce6d3da399

mobile/android/chrome/geckoview/geckoview.js

@@ -15,39 +15,172 @@ XPCOMUtils.defineLazyModuleGetters(this, {
 XPCOMUtils.defineLazyGetter(this, "WindowEventDispatcher",
   () => EventDispatcher.for(window));
 
-// Creates and manages GeckoView modules.
-// A module must extend GeckoViewModule.
-// Instantiate a module by calling
-//   add(<resource path>, <type name>)
-// and remove by calling
-//   remove(<type name>)
+/**
+ * ModuleManager creates and manages GeckoView modules. Each GeckoView module
+ * normally consists of a JSM file with an optional frame script file. The JSM
+ * file contains a class that extends GeckoViewModule. A module usually pairs
+ * with a particular GeckoSessionHandler or delegate on the Java side, and
+ * automatically receives module lifetime events such as initialization, change
+ * in enabled state, and change in settings.
+ */
 var ModuleManager = {
-  init: function(aBrowser) {
-    this.browser = aBrowser;
-    this.modules = new Map();
+  get _initData() {
+    return window.arguments[0].QueryInterface(Ci.nsIAndroidView).initData;
   },
 
-  add: function(aResource, aType, ...aArgs) {
-    this.remove(aType);
+  init(aBrowser, aModules) {
+    const initData = this._initData;
+    this._browser = aBrowser;
+    this._settings = initData.settings;
+    this._frozenSettings = Object.freeze(Object.assign({}, this._settings));
+
+    const self = this;
+    this._modules = new Map((function* () {
+      for (const module of aModules) {
+        yield [
+          module.name,
+          new ModuleInfo({
+            manager: self,
+            ...module,
+          }),
+        ];
+      }
+    })());
+
+    WindowEventDispatcher.registerListener(this, [
+      "GeckoView:EnableModule",
+      "GeckoView:UpdateInitData",
+      "GeckoView:UpdateSettings",
+    ]);
+  },
+
+  get window() {
+    return window;
+  },
+
+  get browser() {
+    return this._browser;
+  },
+
+  get messageManager() {
+    return this._browser.messageManager;
+  },
+
+  get eventDispatcher() {
+    return WindowEventDispatcher;
+  },
+
+  get settings() {
+    return this._frozenSettings;
+  },
+
+  forEach(aCallback) {
+    this._modules.forEach(aCallback, this);
+  },
+
+  _updateSettings(aSettings) {
+    Object.assign(this._settings, aSettings);
+    this._frozenSettings = Object.freeze(Object.assign({}, this._settings));
+
+    this.forEach(module => {
+      if (!module.enabled) {
+        return;
+      }
+      module.impl.onSettingsUpdate();
+      this._browser.messageManager.sendAsyncMessage("GeckoView:UpdateSettings",
+                                                    this._settings);
+    });
+  },
+
+  onEvent(aEvent, aData, aCallback) {
+    switch (aEvent) {
+      case "GeckoView:EnableModule": {
+        const module = this._modules.get(aData.module);
+        if (module) {
+          module.enabled = aData.enabled;
+        }
+        break;
+      }
+
+      case "GeckoView:UpdateInitData": {
+        // Replace all sett_onSettingsUpdateings during a transfer.
+        const initData = this._initData;
+        this._updateSettings(initData.settings);
+        break;
+      }
+
+      case "GeckoView:UpdateSettings": {
+        this._updateSettings(aData);
+        break;
+      }
+    }
+  },
+};
+
+/**
+ * ModuleInfo is the structure used by ModuleManager to represent individual
+ * modules. It is responsible for loading the module JSM file if necessary,
+ * and it acts as the intermediary between ModuleManager and the module
+ * object that extends GeckoViewModule.
+ */
+class ModuleInfo {
+  constructor({manager, name, resource}) {
+    this._manager = manager;
+    this._name = name;
 
     const scope = {};
-    const global = ChromeUtils.import(aResource, scope);
-    const tag = aType.replace("GeckoView", "GeckoView.");
+    const global = ChromeUtils.import(resource, scope);
+    const tag = name.replace("GeckoView", "GeckoView.");
     GeckoViewUtils.initLogging(tag, global);
 
-    this.modules.set(aType, new scope[aType](
-      aType, window, this.browser, WindowEventDispatcher, ...aArgs
-    ));
-  },
-
-  remove: function(aType) {
-    this.modules.delete(aType);
-  },
-
-  forEach: function(aCallback) {
-    this.modules.forEach(aCallback, this);
+    this._impl = new scope[name](this);
+    this._enabled = false;
   }
-};
+
+  onInit() {
+    this._impl.onInit();
+  }
+
+  get manager() {
+    return this._manager;
+  }
+
+  get name() {
+    return this._name;
+  }
+
+  get impl() {
+    return this._impl;
+  }
+
+  get enabled() {
+    return this._enabled;
+  }
+
+  set enabled(aEnabled) {
+    if (aEnabled === this._enabled) {
+      return;
+    }
+
+    if (!aEnabled) {
+      this._manager.messageManager.sendAsyncMessage("GeckoView:Unregister", {
+        module: this._name,
+      });
+      this._impl.onDisable();
+    }
+
+    this._enabled = aEnabled;
+
+    if (aEnabled) {
+      this._impl.onEnable();
+      this._impl.onSettingsUpdate();
+      this._manager.messageManager.sendAsyncMessage("GeckoView:Register", {
+        module: this._name,
+        settings: this._manager.settings,
+      });
+    }
+  }
+}
 
 function createBrowser() {
   const browser = window.browser = document.createElement("browser");
@@ -61,32 +194,39 @@ function startup() {
   GeckoViewUtils.initLogging("GeckoView.XUL", window);
 
   const browser = createBrowser();
-  ModuleManager.init(browser);
-
-  ModuleManager.add("resource://gre/modules/GeckoViewNavigation.jsm",
-                    "GeckoViewNavigation");
-  ModuleManager.add("resource://gre/modules/GeckoViewSettings.jsm",
-                    "GeckoViewSettings");
-  ModuleManager.add("resource://gre/modules/GeckoViewContent.jsm",
-                    "GeckoViewContent");
-  ModuleManager.add("resource://gre/modules/GeckoViewProgress.jsm",
-                    "GeckoViewProgress");
-  ModuleManager.add("resource://gre/modules/GeckoViewScroll.jsm",
-                    "GeckoViewScroll");
-  ModuleManager.add("resource://gre/modules/GeckoViewTab.jsm",
-                    "GeckoViewTab");
-  ModuleManager.add("resource://gre/modules/GeckoViewTrackingProtection.jsm",
-                    "GeckoViewTrackingProtection");
-  ModuleManager.add("resource://gre/modules/GeckoViewSelectionAction.jsm",
-                    "GeckoViewSelectionAction");
-  ModuleManager.add("resource://gre/modules/GeckoViewAccessibility.jsm",
-                    "GeckoViewAccessibility");
+  ModuleManager.init(browser, [{
+    name: "GeckoViewAccessibility",
+    resource: "resource://gre/modules/GeckoViewAccessibility.jsm",
+  }, {
+    name: "GeckoViewContent",
+    resource: "resource://gre/modules/GeckoViewContent.jsm",
+  }, {
+    name: "GeckoViewNavigation",
+    resource: "resource://gre/modules/GeckoViewNavigation.jsm",
+  }, {
+    name: "GeckoViewProgress",
+    resource: "resource://gre/modules/GeckoViewProgress.jsm",
+  }, {
+    name: "GeckoViewScroll",
+    resource: "resource://gre/modules/GeckoViewScroll.jsm",
+  }, {
+    name: "GeckoViewSelectionAction",
+    resource: "resource://gre/modules/GeckoViewSelectionAction.jsm",
+  }, {
+    name: "GeckoViewSettings",
+    resource: "resource://gre/modules/GeckoViewSettings.jsm",
+  }, {
+    name: "GeckoViewTab",
+    resource: "resource://gre/modules/GeckoViewTab.jsm",
+  }, {
+    name: "GeckoViewTrackingProtection",
+    resource: "resource://gre/modules/GeckoViewTrackingProtection.jsm",
+  }]);
 
   window.document.documentElement.appendChild(browser);
 
   ModuleManager.forEach(module => {
     module.onInit();
-    module.onSettingsUpdate();
   });
 
   // Move focus to the content window at the end of startup,

mobile/android/modules/geckoview/GeckoViewModule.jsm

@@ -12,45 +12,43 @@ ChromeUtils.import("resource://gre/modules/GeckoViewUtils.jsm");
 GeckoViewUtils.initLogging("GeckoView.Module", this);
 
 class GeckoViewModule {
-  constructor(aModuleName, aWindow, aBrowser, aEventDispatcher) {
-    this.isRegistered = false;
-    this.window = aWindow;
-    this.browser = aBrowser;
-    this.eventDispatcher = aEventDispatcher;
-    this.moduleName = aModuleName;
+  constructor(aModuleInfo) {
+    this._info = aModuleInfo;
+
     this._isContentLoaded = false;
     this._eventProxy = new EventProxy(this, this.eventDispatcher);
 
-    this.eventDispatcher.registerListener(
-      (aEvent, aData, aCallback) => {
-        this.messageManager.sendAsyncMessage("GeckoView:UpdateSettings",
-                                             this.settings);
-        this.onSettingsUpdate();
-      }, "GeckoView:UpdateSettings"
-    );
-
-    this.eventDispatcher.registerListener(
-      (aEvent, aData, aCallback) => {
-        if (aData.module == this.moduleName) {
-          this._register();
-          aData.settings = this.settings;
-          this.messageManager.sendAsyncMessage("GeckoView:Register", aData);
-        }
-      }, "GeckoView:Register"
-    );
-
-    this.eventDispatcher.registerListener(
-      (aEvent, aData, aCallback) => {
-        if (aData.module == this.moduleName) {
-          this.messageManager.sendAsyncMessage("GeckoView:Unregister", aData);
-          this._unregister();
-        }
-      }, "GeckoView:Unregister"
-    );
-
     this.onInitBrowser();
   }
 
+  get name() {
+    return this._info.name;
+  }
+
+  get enabled() {
+    return this._info.enabled;
+  }
+
+  get window() {
+    return this._info.manager.window;
+  }
+
+  get browser() {
+    return this._info.manager.browser;
+  }
+
+  get messageManager() {
+    return this._info.manager.messageManager;
+  }
+
+  get eventDispatcher() {
+    return this._info.manager.eventDispatcher;
+  }
+
+  get settings() {
+    return this._info.manager.settings;
+  }
+
   // Override to initialize the browser before it is bound to the window.
   onInitBrowser() {}
 
@@ -66,22 +64,6 @@ class GeckoViewModule {
   // Override to disable module after clearing the Java delegate.
   onDisable() {}
 
-  _register() {
-    if (this.isRegistered) {
-      return;
-    }
-    this.onEnable();
-    this.isRegistered = true;
-  }
-
-  _unregister() {
-    if (!this.isRegistered) {
-      return;
-    }
-    this.onDisable();
-    this.isRegistered = false;
-  }
-
   registerContent(aUri) {
     if (this._isContentLoaded) {
       return;
@@ -92,7 +74,7 @@ class GeckoViewModule {
     let self = this;
     this.messageManager.addMessageListener("GeckoView:ContentRegistered",
       function listener(aMsg) {
-        if (aMsg.data.module !== self.moduleName) {
+        if (aMsg.data.module !== self.name) {
           return;
         }
         self.messageManager.removeMessageListener("GeckoView:ContentRegistered",
@@ -110,15 +92,6 @@ class GeckoViewModule {
   unregisterListener() {
     this._eventProxy.unregisterListener();
   }
-
-  get settings() {
-    let view = this.window.arguments[0].QueryInterface(Ci.nsIAndroidView);
-    return Object.freeze(view.settings);
-  }
-
-  get messageManager() {
-    return this.browser.messageManager;
-  }
 }
 
 class EventProxy {

mobile/android/modules/geckoview/GeckoViewNavigation.jsm

@@ -123,7 +123,7 @@ class GeckoViewNavigation extends GeckoViewModule {
     debug `handleNewSession: uri=${aUri && aUri.spec}
                              where=${aWhere} flags=${aFlags}`;
 
-    if (!this.isRegistered) {
+    if (!this.enabled) {
       return null;
     }