Find target for new window downloads based on the channel

juggler/TargetRegistry.js

@@ -25,13 +25,29 @@ class DownloadInterceptor {
   constructor(registry) {
     this._registry = registry
     this._handlerToUuid = new Map();
+    helper.addObserver(this._onRequest.bind(this), 'http-on-modify-request');
+  }
+
+  _onRequest(httpChannel, topic) {
+    let loadContext = helper.getLoadContext(httpChannel);
+    if (!loadContext)
+      return;
+    if (!loadContext.topFrameElement)
+      return;
+    const target = this._registry.targetForBrowser(loadContext.topFrameElement);
+    if (!target)
+      return;
+    target._channelIds.add(httpChannel.channelId);
   }
 
   //
   // nsIDownloadInterceptor implementation.
   //
   interceptDownloadRequest(externalAppHandler, request, browsingContext, outFile) {
-    const pageTarget = this._registry._browserBrowsingContextToTarget.get(browsingContext);
+    let pageTarget = this._registry._browserBrowsingContextToTarget.get(browsingContext);
+    // New page downloads won't have browsing contex.
+    if (!pageTarget)
+      pageTarget = this._registry._targetForChannel(request);
     if (!pageTarget)
       return false;
 
@@ -284,6 +300,15 @@ class TargetRegistry {
   targetForBrowser(browser) {
     return this._browserToTarget.get(browser);
   }
+
+  _targetForChannel(channel) {
+    const channelId = channel.channelId;
+    for (const target of this._browserToTarget.values()) {
+      if (target._channelIds.has(channelId))
+        return target;
+    }
+    return null;
+  }
 }
 
 class PageTarget {
@@ -299,6 +324,7 @@ class PageTarget {
     this._url = '';
     this._openerId = opener ? opener.id() : undefined;
     this._channel = SimpleChannel.createForMessageManager(`browser::page[${this._targetId}]`, this._linkedBrowser.messageManager);
+    this._channelIds = new Set();
 
     const navigationListener = {
       QueryInterface: ChromeUtils.generateQI([ Ci.nsIWebProgressListener]),

juggler/content/FrameTree.js

@@ -222,7 +222,7 @@ class FrameTree {
       // Always report download navigation as failure to match other browsers.
       const errorText = isDownload ? 'Will download to file' : helper.getNetworkErrorStatusText(status);
       this.emit(FrameTree.Events.NavigationAborted, frame, navigationId, errorText);
-      if (frame === this._mainFrame && status !== Cr.NS_BINDING_ABORTED)
+      if (frame === this._mainFrame && status !== Cr.NS_BINDING_ABORTED && !isDownload)
         this.forcePageReady();
     }
   }