browser(firefox): enable document channel (#4065)

In the current tip-of-tree Firefox, document channel is enabled by
default, so we have to enable it in order to roll further.

This patch:
1. Removes content disposition sniffing from content process since it
   crashes renderer with document channel.
2. Merges all page-related handlers in a single `PageHandler` and
   serializes network events wrt the `Page.frameAttached` event.

The serialization mentioned in (2) is necessary: frame attachment is
reported from the content process, and network events are reported from
the browsers process. This is an inherent race, that becomes exposed by
the document channel.

On a side note, (2) makes it possible to synchronously report all
buffered events in `SimpleChannel` (cc offline discussion with @dgozman
that highlighted an unsighty approach that we currently employ there: reporting
events in a subsequent microtask.)

References #3995

Author: aslushnikov

browser_patches/firefox/BUILD_NUMBER

@@ -1,2 +1,2 @@
-1181
-Changed: [email protected] Mon, Oct  5, 2020  5:57:35 PM
+1182
+Changed: [email protected] Mon Oct  5 23:55:54 PDT 2020

browser_patches/firefox/juggler/NetworkObserver.js

@@ -128,25 +128,36 @@ class NetworkRequest {
     this.httpChannel = httpChannel;
     this._networkObserver._channelToRequest.set(this.httpChannel, this);
 
+    const loadInfo = this.httpChannel.loadInfo;
+    let browsingContext = loadInfo?.frameBrowsingContext || loadInfo?.browsingContext;
+    // TODO: Unfortunately, requests from web workers don't have frameBrowsingContext or
+    // browsingContext.
+    //
+    // We fail to attribute them to the original frames on the browser side, but we
+    // can use load context top frame to attribute them to the top frame at least.
+    if (!browsingContext) {
+      const loadContext = helper.getLoadContext(this.httpChannel);
+      browsingContext = loadContext?.topFrameElement?.browsingContext;
+    }
+
+    this._frameId = helper.browsingContextToFrameId(browsingContext);
+
     this.requestId = httpChannel.channelId + '';
     this.navigationId = httpChannel.isMainDocumentChannel ? this.requestId : undefined;
 
     const internalCauseType = this.httpChannel.loadInfo ? this.httpChannel.loadInfo.internalContentPolicyType : Ci.nsIContentPolicy.TYPE_OTHER;
-    this.channelKey = this.httpChannel.channelId + ':' + internalCauseType;
 
     this._redirectedIndex = 0;
     const ignoredRedirect = redirectedFrom && !redirectedFrom._sentOnResponse;
     if (ignoredRedirect) {
       // We just ignore redirect that did not hit the network before being redirected.
       // This happens, for example, for automatic http->https redirects.
       this.navigationId = redirectedFrom.navigationId;
-      this.channelKey = redirectedFrom.channelKey;
     } else if (redirectedFrom) {
       this.redirectedFromId = redirectedFrom.requestId;
       this._redirectedIndex = redirectedFrom._redirectedIndex + 1;
       this.requestId = this.requestId + '-redirect' + this._redirectedIndex;
       this.navigationId = redirectedFrom.navigationId;
-      this.channelKey = redirectedFrom.channelKey;
       // Finish previous request now. Since we inherit the listener, we could in theory
       // use onStopRequest, but that will only happen after the last redirect has finished.
       redirectedFrom._sendOnRequestFinished();
@@ -492,21 +503,9 @@ class NetworkRequest {
     const loadInfo = this.httpChannel.loadInfo;
     const causeType = loadInfo?.externalContentPolicyType || Ci.nsIContentPolicy.TYPE_OTHER;
     const internalCauseType = loadInfo?.internalContentPolicyType || Ci.nsIContentPolicy.TYPE_OTHER;
-
-    let browsingContext = loadInfo?.frameBrowsingContext || loadInfo?.browsingContext;
-    // TODO: Unfortunately, requests from web workers don't have frameBrowsingContext or
-    // browsingContext.
-    //
-    // We fail to attribute them to the original frames on the browser side, but we
-    // can use load context top frame to attribute them to the top frame at least.
-    if (!browsingContext) {
-      const loadContext = helper.getLoadContext(this.httpChannel);
-      browsingContext = loadContext?.topFrameElement?.browsingContext;
-    }
-
     pageNetwork.emit(PageNetwork.Events.Request, {
       url: this.httpChannel.URI.spec,
-      frameId: helper.browsingContextToFrameId(browsingContext),
+      frameId: this._frameId,
       isIntercepted,
       requestId: this.requestId,
       redirectedFrom: this.redirectedFromId,
@@ -516,7 +515,7 @@ class NetworkRequest {
       navigationId: this.navigationId,
       cause: causeTypeToString(causeType),
       internalCause: causeTypeToString(internalCauseType),
-    }, this.channelKey);
+    }, this._frameId);
   }
 
   _sendOnResponse(fromCache) {
@@ -563,7 +562,7 @@ class NetworkRequest {
       remotePort,
       status,
       statusText,
-    });
+    }, this._frameId);
   }
 
   _sendOnRequestFailed(error) {
@@ -572,7 +571,7 @@ class NetworkRequest {
       pageNetwork.emit(PageNetwork.Events.RequestFailed, {
         requestId: this.requestId,
         errorCode: helper.getNetworkErrorStatusText(error),
-      });
+      }, this._frameId);
     }
     this._networkObserver._channelToRequest.delete(this.httpChannel);
   }
@@ -582,7 +581,7 @@ class NetworkRequest {
     if (pageNetwork) {
       pageNetwork.emit(PageNetwork.Events.RequestFinished, {
         requestId: this.requestId,
-      });
+      }, this._frameId);
     }
     this._networkObserver._channelToRequest.delete(this.httpChannel);
   }

browser_patches/firefox/juggler/TargetRegistry.js

@@ -26,29 +26,16 @@ 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) {
-    let pageTarget = this._registry._browserBrowsingContextToTarget.get(browsingContext);
-    // New page downloads won't have browsing contex.
-    if (!pageTarget)
-      pageTarget = this._registry._targetForChannel(request);
+    if (!(request instanceof Ci.nsIChannel))
+      return false;
+    const channel = request.QueryInterface(Ci.nsIChannel);
+    let pageTarget = this._registry._browserBrowsingContextToTarget.get(channel.loadInfo.browsingContext);
     if (!pageTarget)
       return false;
 
@@ -324,15 +311,6 @@ 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 {
@@ -350,7 +328,6 @@ class PageTarget {
     this._url = 'about:blank';
     this._openerId = opener ? opener.id() : undefined;
     this._channel = SimpleChannel.createForMessageManager(`browser::page[${this._targetId}]`, this._linkedBrowser.messageManager);
-    this._channelIds = new Set();
     this._screencastInfo = undefined;
 
     const navigationListener = {

browser_patches/firefox/juggler/components/juggler.js

@@ -73,7 +73,7 @@ CommandLineHandler.prototype = {
             if (silent)
               Services.startup.exitLastWindowClosingSurvivalArea();
           });
-          dispatcher.rootSession().registerHandler('Browser', browserHandler);
+          dispatcher.rootSession().setHandler(browserHandler);
         }
       });
       loadFrameScript();
@@ -101,9 +101,9 @@ CommandLineHandler.prototype = {
           pipe.stop();
         });
       });
-      dispatcher.rootSession().registerHandler('Browser', browserHandler);
+      dispatcher.rootSession().setHandler(browserHandler);
       loadFrameScript();
-      dump(`Juggler listening to the pipe\n`);
+      dump(`\nJuggler listening to the pipe\n`);
     }
   },
 

browser_patches/firefox/juggler/content/FrameTree.js

@@ -197,19 +197,12 @@ class FrameTree {
     const isTransferring = flag & Ci.nsIWebProgressListener.STATE_TRANSFERRING;
     const isStop = flag & Ci.nsIWebProgressListener.STATE_STOP;
 
-    let isDownload = false;
-    try {
-      isDownload = (channel.contentDisposition === Ci.nsIChannel.DISPOSITION_ATTACHMENT);
-    } catch(e) {
-      // The method is expected to throw if it's not an attachment.
-    }
-
     if (isStart) {
       // Starting a new navigation.
       frame._pendingNavigationId = this._channelId(channel);
       frame._pendingNavigationURL = channel.URI.spec;
       this.emit(FrameTree.Events.NavigationStarted, frame);
-    } else if (isTransferring || (isStop && frame._pendingNavigationId && !status && !isDownload)) {
+    } else if (isTransferring || (isStop && frame._pendingNavigationId && !status)) {
       // Navigation is committed.
       for (const subframe of frame._children)
         this._detachFrame(subframe);
@@ -221,15 +214,15 @@ class FrameTree {
       this.emit(FrameTree.Events.NavigationCommitted, frame);
       if (frame === this._mainFrame)
         this.forcePageReady();
-    } else if (isStop && frame._pendingNavigationId && (status || isDownload)) {
+    } else if (isStop && frame._pendingNavigationId && status) {
       // Navigation is aborted.
       const navigationId = frame._pendingNavigationId;
       frame._pendingNavigationId = null;
       frame._pendingNavigationURL = null;
       // Always report download navigation as failure to match other browsers.
-      const errorText = isDownload ? 'Will download to file' : helper.getNetworkErrorStatusText(status);
+      const errorText = helper.getNetworkErrorStatusText(status);
       this.emit(FrameTree.Events.NavigationAborted, frame, navigationId, errorText);
-      if (frame === this._mainFrame && status !== Cr.NS_BINDING_ABORTED && !isDownload)
+      if (frame === this._mainFrame && status !== Cr.NS_BINDING_ABORTED)
         this.forcePageReady();
     }
   }
@@ -245,9 +238,9 @@ class FrameTree {
   }
 
   _channelId(channel) {
-    if (channel instanceof Ci.nsIHttpChannel) {
-      const httpChannel = channel.QueryInterface(Ci.nsIHttpChannel);
-      return String(httpChannel.channelId);
+    if (channel instanceof Ci.nsIIdentChannel) {
+      const identChannel = channel.QueryInterface(Ci.nsIIdentChannel);
+      return String(identChannel.channelId);
     }
     return helper.generateId();
   }

browser_patches/firefox/juggler/jar.mn

@@ -12,10 +12,7 @@ juggler.jar:
   content/protocol/Protocol.js (protocol/Protocol.js)
   content/protocol/Dispatcher.js (protocol/Dispatcher.js)
   content/protocol/PageHandler.js (protocol/PageHandler.js)
-  content/protocol/RuntimeHandler.js (protocol/RuntimeHandler.js)
-  content/protocol/NetworkHandler.js (protocol/NetworkHandler.js)
   content/protocol/BrowserHandler.js (protocol/BrowserHandler.js)
-  content/protocol/AccessibilityHandler.js (protocol/AccessibilityHandler.js)
   content/content/main.js (content/main.js)
   content/content/FrameTree.js (content/FrameTree.js)
   content/content/PageAgent.js (content/PageAgent.js)