Fix embedder only getting events for webContents when attached to a w…

…ebview. Each time a webContents gets a new embedder contents (window), it will register with it.

Introduce 'set-window' and 'guest-created' WebContents events.

Fix #515

atom/browser/extensions/tab_helper.cc

@@ -468,6 +468,9 @@ void TabHelper::SetWindowId(const int32_t& id) {
   SessionID session;
   session.set_id(id);
   SessionTabHelper::FromWebContents(web_contents())->SetWindowID(session);
+  if (guest()) {
+    guest()->WindowIdChanged();
+  }
 }
 
 int32_t TabHelper::window_id() const {

brave/browser/guest_view/tab_view/tab_view_guest.cc

@@ -232,6 +232,17 @@ void TabViewGuest::TabIdChanged() {
       "webViewInternal.onTabIdChanged", std::move(args)));
 }
 
+void TabViewGuest::WindowIdChanged() {
+  DCHECK(api_web_contents_);
+  if (api_web_contents_) {
+    if (owner_web_contents()) {
+      api_web_contents_->Emit("set-window", owner_web_contents());
+      return;
+    }
+    api_web_contents_->Emit("set-window");
+  }
+}
+
 void TabViewGuest::DidInitialize(const base::DictionaryValue& create_params) {
   v8::Isolate* isolate = v8::Isolate::GetCurrent();
   v8::Locker locker(isolate);
@@ -346,6 +357,7 @@ void TabViewGuest::ApplyAttributes(const base::DictionaryValue& params) {
       }
     }
   }
+  api_web_contents_->Emit("guest-created", owner_web_contents());
 }
 
 void TabViewGuest::DidAttachToEmbedder() {

brave/browser/guest_view/tab_view/tab_view_guest.h

@@ -31,7 +31,8 @@ class TabViewGuest : public guest_view::GuestView<TabViewGuest> {
   void DetachGuest();
   void SetCanRunInDetachedState(bool can_run_detached);
   void TabIdChanged();
-
+  void WindowIdChanged();
+
   void Load();
 
  private:

lib/browser/api/web-contents.js

@@ -201,8 +201,12 @@ WebContents.prototype._init = function () {
     this.reload()
   })
 
-  this.on('will-attach', function (event, embedder) {
-    guestViewManager.registerGuest(event.sender, embedder)
+  this.on('set-window', function (event, embedder) {
+    if (embedder) {
+      guestViewManager.registerGuest(event.sender, embedder)
+    } else {
+      guestViewManager.deregisterGuest(event.sender)
+    }
   })
 
   if (!this.isRemote()) {

lib/browser/guest-view-manager.js

@@ -7,6 +7,8 @@ let supportedWebViewEvents = [
   'tab-replaced-at',
   'load-start',
   'did-attach',
+  'set-window-id',
+  'guest-created',
   'guest-ready',
   'will-detach',
   'did-detach',
@@ -45,53 +47,114 @@ let supportedWebViewEvents = [
 ]
 
 let guests = {}
+// ensure webcontent events (from guest) are fired to embedder (window) so they can be forwarded to webview / interested-party
 const registerGuest = function (guest, embedder) {
   const tabId = guest.getId()
+
+  const oldEmbedderDetails = guests[tabId]
+
+  const isNewEmbedder = !oldEmbedderDetails || oldEmbedderDetails.embedder !== embedder
 
-  embedder.once('destroyed', function () {
-    if (guests[tabId] === embedder) {
+  // Events were previously setup and we don't have a different embedder
+  if (oldEmbedderDetails && !isNewEmbedder) {
+    return
+  }
+
+  if (!oldEmbedderDetails) {
+    guests[tabId] = {}
+  }
+  // always update the embedder so events get routed to the correct window
+  guests[tabId].embedder = embedder
+  // listen for destroyed event on new embedders
+  const destroyedListener = function () {
+    if (guests[tabId] && guests[tabId].embedder === embedder) {
+      const guestHandlers = guests[tabId].guestHandlers
       guests[tabId] = false
+      // remove handlers
+      // since now that the reference is reset,
+      // next time tab is attached, new handlers will be created
+      if (guest && !guest.isDestroyed()) {
+        for (const event in guestHandlers) {
+          guest.removeListener(event, guestHandlers[event])
+        }
+      }
     }
-  })
+  }
+  embedder.once('destroyed', destroyedListener)
 
-  const oldEmbedder = guests[tabId]
-  guests[tabId] = embedder
-  if (oldEmbedder !== undefined) {
+  // Events were previously setup, but we have a new embedder
+  if (oldEmbedderDetails && isNewEmbedder) {
+    // stop listening to destroyed event on the embedder
+    oldEmbedderDetails.embedder.removeListener('destroyed', oldEmbedderDetails.destroyedListener)
+    // remember the new embedders destroy listener, so we can remove that
+    // next time the embedder changes
+    guests[tabId].destroyedListener = destroyedListener
+    // no need to re-attach event listeners if we've already done that, the events
+    // will dispatch to the new embedder when they fire
     return
   }
 
+  guests[tabId].destroyedListener = destroyedListener
+
   // Dispatch events to embedder.
-  const fn = function (event) {
-    guest.on(event, function (_, ...args) {
-      const embedder = guests[tabId]
+  const guestHandlers = { }
+  for (const event of supportedWebViewEvents) {
+    guestHandlers[event] = function (_, ...args) {
+      const embedder = guests[tabId] && guests[tabId].embedder
 
       if (!embedder || embedder.isDestroyed())
         return
 
       let forceSend = false
-      if (['destroyed', 'did-detach', 'will-detach'].includes(event)) {
+      if (['destroyed'].includes(event)) {
         delete guests[tabId]
         forceSend = true
       }
 
-      if (guest.isDestroyed() && !forceSend)
+      if (guest.isDestroyed() && !forceSend) {
         return
+      }
 
       embedder.send.apply(embedder, ['ELECTRON_GUEST_VIEW_INTERNAL_DISPATCH_EVENT', tabId, event].concat(args))
-    })
-  }
-  for (const event of supportedWebViewEvents) {
-    fn(event)
+    }
+    guest.on(event, guestHandlers[event])
   }
-
-  // Dispatch guest's IPC messages to embedder.
-  guest.on('ipc-message-host', function (_, [channel, ...args]) {
-    const embedder = guests[tabId]
+  const handleIpcMessage = function (_, [channel, ...args]) {
+    const embedder = guests[tabId] && guests[tabId].embedder
     if (!embedder || embedder.isDestroyed() || guest.isDestroyed())
       return
 
     embedder.send.apply(embedder, ['ELECTRON_GUEST_VIEW_INTERNAL_IPC_MESSAGE', tabId, channel].concat(args))
-  })
+  }
+  // Dispatch guest's IPC messages to embedder.
+  guest.on('ipc-message-host', handleIpcMessage)
+  guestHandlers['ipc-message-host'] = handleIpcMessage
+  // store handlers so we can deregister them when:
+  // - embedder is destroyed
+  // - guest does not have an embedder at all
+  guests[tabId].guestHandlers = guestHandlers
+}
+
+const deregisterGuest = function (guest) {
+  if (!guest || guest.isDestroyed()) {
+    return
+  }
+  const tabId = guest.getId()
+  const embedderDetails = guests[tabId]
+  if (!embedderDetails) {
+    return
+  }
+  guests[tabId] = false
+  const guestHandlers = guests[tabId].guestHandlers
+  if (guestHandlers) {
+    for (const event in guestHandlers) {
+      guest.removeListener(event, guestHandlers[event])
+    }
+  }
+  if (embedderDetails.embedder && embedderDetails.destroyedListener) {
+    embedderDetails.embedder.removeListener('destroyed', embedderDetails.destroyedListener)
+  }
 }
 
 exports.registerGuest = registerGuest
+exports.deregisterGuest = deregisterGuest

lib/renderer/web-view/guest-view-internal.js

@@ -8,6 +8,8 @@ var WEB_VIEW_EVENTS = {
   'load-start': ['url', 'isMainFrame', 'isErrorPage'],
   'will-detach': [],
   'did-attach': ['tabId'],
+  'guest-created': ['embedderWebContents'],
+  'set-window-id': ['embedderWebContents'],
   'guest-ready': ['tabId', 'guestInstanceId'],
   'did-detach': [],
   'did-finish-load': ['validatedURL'],
@@ -50,6 +52,9 @@ var dispatchEvent = function (tabId, eventName, ...args) {
   var domEvent, f, i, j, len, ref1
   domEvent = new Event(eventName)
   ref1 = WEB_VIEW_EVENTS[eventName]
+  if (!ref1) {
+    return
+  }
   for (i = j = 0, len = ref1.length; j < len; i = ++j) {
     f = ref1[i]
     domEvent[f] = args[i]