Bug 1633644 - P2. Do not call RedirectToRealChannel if the channel got cancelled. r=mattwoodrow.

Depends on D72795

Differential Revision: https://phabricator.services.mozilla.com/D72809

netwerk/ipc/DocumentLoadListener.cpp

@@ -700,6 +700,8 @@ void DocumentLoadListener::Cancel(const nsresult& aStatusCode) {
       ("DocumentLoadListener Cancel [this=%p, "
        "aStatusCode=%" PRIx32 " ]",
        this, static_cast<uint32_t>(aStatusCode)));
+  mCancelled = true;
+
   if (mDoingProcessSwitch) {
     // If we've already initiated process-switching
     // then we can no longer be cancelled and we'll
@@ -1431,8 +1433,13 @@ DocumentLoadListener::RedirectToRealChannel(
 
   return EnsureBridge()->Then(
       GetCurrentThreadSerialEventTarget(), __func__,
-      [endpoints = std::move(aStreamFilterEndpoints), aRedirectFlags,
+      [self = RefPtr<DocumentLoadListener>(this),
+       endpoints = std::move(aStreamFilterEndpoints), aRedirectFlags,
        aLoadFlags](ADocumentChannelBridge* aBridge) mutable {
+        if (self->mCancelled) {
+          return PDocumentChannelParent::RedirectToRealChannelPromise::
+              CreateAndResolve(NS_BINDING_ABORTED, __func__);
+        }
         return aBridge->RedirectToRealChannel(std::move(endpoints),
                                               aRedirectFlags, aLoadFlags);
       },

netwerk/ipc/DocumentLoadListener.h

@@ -434,6 +434,9 @@ class DocumentLoadListener : public nsIInterfaceRequestor,
   // This identifier is set by MaybeTriggerProcessSwitch, and is later
   // passed to the childChannel in order to identify it in the new process.
   uint64_t mCrossProcessRedirectIdentifier = 0;
+
+  // True if cancelled.
+  bool mCancelled = false;
 };
 
 NS_DEFINE_STATIC_IID_ACCESSOR(DocumentLoadListener, DOCUMENT_LOAD_LISTENER_IID)