new file mode 100644
--- /dev/null
+++ b/netwerk/base/src/ChannelDiverterChild.cpp
@@ -0,0 +1,27 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "mozilla/net/ChannelDiverterChild.h"
+#include "mozilla/net/NeckoChannelParams.h"
+#include "mozilla/net/HttpChannelChild.h"
+#include "mozilla/net/FTPChannelChild.h"
+#include "mozilla/net/PHttpChannelChild.h"
+#include "mozilla/net/PFTPChannelChild.h"
+#include "nsIDivertableChannel.h"
+
+namespace mozilla {
+namespace net {
+
+ChannelDiverterChild::ChannelDiverterChild()
+{
+}
+
+ChannelDiverterChild::~ChannelDiverterChild()
+{
+}
+
+} // namespace net
+} // namespace mozilla

new file mode 100644
--- /dev/null
+++ b/netwerk/base/src/ChannelDiverterChild.h
@@ -0,0 +1,30 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef _channeldiverterchild_h_
+#define _channeldiverterchild_h_
+
+#include "mozilla/net/PChannelDiverterChild.h"
+
+class nsIDivertableChannel;
+
+namespace mozilla {
+namespace net {
+
+class ChannelDiverterArgs;
+
+class ChannelDiverterChild :
+  public PChannelDiverterChild
+{
+public:
+  ChannelDiverterChild();
+  virtual ~ChannelDiverterChild();
+};
+
+} // namespace net
+} // namespace mozilla
+
+#endif /* _channeldiverterchild_h_ */

new file mode 100644
--- /dev/null
+++ b/netwerk/base/src/ChannelDiverterParent.cpp
@@ -0,0 +1,65 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "mozilla/net/ChannelDiverterParent.h"
+#include "mozilla/net/NeckoChannelParams.h"
+#include "mozilla/net/HttpChannelParent.h"
+#include "mozilla/net/FTPChannelParent.h"
+#include "mozilla/net/PHttpChannelParent.h"
+#include "mozilla/net/PFTPChannelParent.h"
+#include "ADivertableParentChannel.h"
+
+namespace mozilla {
+namespace net {
+
+ChannelDiverterParent::ChannelDiverterParent()
+{
+}
+
+ChannelDiverterParent::~ChannelDiverterParent()
+{
+}
+
+bool
+ChannelDiverterParent::Init(const ChannelDiverterArgs& aChannel)
+{
+  switch (aChannel.type()) {
+  case ChannelDiverterArgs::TPHttpChannelParent:
+  {
+    mDivertableChannelParent = static_cast<ADivertableParentChannel*>(
+      static_cast<HttpChannelParent*>(aChannel.get_PHttpChannelParent()));
+    break;
+  }
+  case ChannelDiverterArgs::TPFTPChannelParent:
+  {
+    mDivertableChannelParent = static_cast<ADivertableParentChannel*>(
+      static_cast<FTPChannelParent*>(aChannel.get_PFTPChannelParent()));
+    break;
+  }
+  default:
+    NS_NOTREACHED("unknown ChannelDiverterArgs type");
+    return false;
+  }
+  MOZ_ASSERT(mDivertableChannelParent);
+
+  nsresult rv = mDivertableChannelParent->SuspendForDiversion();
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return false;
+  }
+  return true;
+}
+
+void
+ChannelDiverterParent::DivertTo(nsIStreamListener* newListener)
+{
+  MOZ_ASSERT(newListener);
+  MOZ_ASSERT(mDivertableChannelParent);
+
+  mDivertableChannelParent->DivertTo(newListener);
+}
+
+} // namespace net
+} // namespace mozilla

new file mode 100644
--- /dev/null
+++ b/netwerk/base/src/ChannelDiverterParent.h
@@ -0,0 +1,37 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef _channeldiverterparent_h_
+#define _channeldiverterparent_h_
+
+#include "mozilla/net/PChannelDiverterParent.h"
+
+class nsIStreamListener;
+
+namespace mozilla {
+namespace net {
+
+class ChannelDiverterArgs;
+class ADivertableParentChannel;
+
+class ChannelDiverterParent :
+  public PChannelDiverterParent
+{
+public:
+  ChannelDiverterParent();
+  virtual ~ChannelDiverterParent();
+
+  bool Init(const ChannelDiverterArgs& aChannel);
+
+  void DivertTo(nsIStreamListener* newListener);
+private:
+  nsRefPtr<ADivertableParentChannel> mDivertableChannelParent;
+};
+
+} // namespace net
+} // namespace mozilla
+
+#endif /* _channeldiverterparent_h_ */

--- a/netwerk/base/src/moz.build
+++ b/netwerk/base/src/moz.build
@@ -7,23 +7,27 @@
 EXPORTS += [
     'nsFileStreams.h',
     'nsMIMEInputStream.h',
     'nsTemporaryFileInputStream.h',
     'nsURLHelper.h',
 ]
 
 EXPORTS.mozilla.net += [
+    'ChannelDiverterChild.h',
+    'ChannelDiverterParent.h',
     'Dashboard.h',
     'DashboardTypes.h',
 ]
 
 UNIFIED_SOURCES += [
     'ArrayBufferInputStream.cpp',
     'BackgroundFileSaver.cpp',
+    'ChannelDiverterChild.cpp',
+    'ChannelDiverterParent.cpp',
     'Dashboard.cpp',
     'EventTokenBucket.cpp',
     'LoadContextInfo.cpp',
     'NetworkActivityMonitor.cpp',
     'nsAsyncStreamCopier.cpp',
     'nsAuthInformationHolder.cpp',
     'nsBase64Encoder.cpp',
     'nsBaseChannel.cpp',
@@ -108,16 +112,17 @@ FAIL_ON_WARNINGS = True
 
 MSVC_ENABLE_PGO = True
 
 include('/ipc/chromium/chromium-config.mozbuild')
 
 FINAL_LIBRARY = 'necko'
 LOCAL_INCLUDES += [
     '/dom/base',
+    '/netwerk/protocol/http'
 ]
 
 if 'rtsp' in CONFIG['NECKO_PROTOCOLS']:
     LOCAL_INCLUDES += [
         '/netwerk/protocol/rtsp/controller',
         '/netwerk/protocol/rtsp/rtsp',
     ]
 

--- a/netwerk/ipc/NeckoChannelParams.ipdlh
+++ b/netwerk/ipc/NeckoChannelParams.ipdlh
@@ -1,15 +1,17 @@
 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
 /* vim: set sw=2 ts=8 et tw=80 ft=c: */
 
 /* This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
+include protocol PHttpChannel;
+include protocol PFTPChannel;
 include URIParams;
 include InputStreamParams;
 
 using struct mozilla::void_t from "ipc/IPCMessageUtils.h";
 using RequestHeaderTuples from "mozilla/net/PHttpChannelParams.h";
 using struct nsHttpAtom from "nsHttp.h";
 
 namespace mozilla {
@@ -75,10 +77,16 @@ struct FTPChannelConnectArgs
 };
 
 union FTPChannelCreationArgs
 {
   FTPChannelOpenArgs;      // For AsyncOpen: the common case.
   FTPChannelConnectArgs;   // Used for redirected-to channels
 };
 
+union ChannelDiverterArgs
+{
+  PHttpChannel;
+  PFTPChannel;
+};
+
 } // namespace ipc
 } // namespace mozilla

--- a/netwerk/ipc/NeckoChild.cpp
+++ b/netwerk/ipc/NeckoChild.cpp
@@ -11,16 +11,17 @@
 #include "mozilla/dom/ContentChild.h"
 #include "mozilla/net/HttpChannelChild.h"
 #include "mozilla/net/CookieServiceChild.h"
 #include "mozilla/net/WyciwygChannelChild.h"
 #include "mozilla/net/FTPChannelChild.h"
 #include "mozilla/net/WebSocketChannelChild.h"
 #include "mozilla/net/DNSRequestChild.h"
 #include "mozilla/net/RemoteOpenFileChild.h"
+#include "mozilla/net/ChannelDiverterChild.h"
 #include "mozilla/dom/network/TCPSocketChild.h"
 #include "mozilla/dom/network/TCPServerSocketChild.h"
 #include "mozilla/dom/network/UDPSocketChild.h"
 #ifdef NECKO_PROTOCOL_rtsp
 #include "mozilla/net/RtspControllerChild.h"
 #endif
 #include "SerializedLoadContext.h"
 
@@ -261,10 +262,23 @@ NeckoChild::AllocPRemoteOpenFileChild(co
 bool
 NeckoChild::DeallocPRemoteOpenFileChild(PRemoteOpenFileChild* aChild)
 {
   RemoteOpenFileChild *p = static_cast<RemoteOpenFileChild*>(aChild);
   p->ReleaseIPDLReference();
   return true;
 }
 
+PChannelDiverterChild*
+NeckoChild::AllocPChannelDiverterChild(const ChannelDiverterArgs& channel)
+{
+  return new ChannelDiverterChild();;
+}
+
+bool
+NeckoChild::DeallocPChannelDiverterChild(PChannelDiverterChild* child)
+{
+  delete static_cast<ChannelDiverterChild*>(child);
+  return true;
+}
+
 }} // mozilla::net
 

--- a/netwerk/ipc/NeckoChild.h
+++ b/netwerk/ipc/NeckoChild.h
@@ -57,16 +57,20 @@ protected:
                                                   const uint32_t& aFlags) MOZ_OVERRIDE;
   virtual bool DeallocPDNSRequestChild(PDNSRequestChild*) MOZ_OVERRIDE;
   virtual PRemoteOpenFileChild*
     AllocPRemoteOpenFileChild(const URIParams&,
                               const OptionalURIParams&) MOZ_OVERRIDE;
   virtual bool DeallocPRemoteOpenFileChild(PRemoteOpenFileChild*) MOZ_OVERRIDE;
   virtual PRtspControllerChild* AllocPRtspControllerChild() MOZ_OVERRIDE;
   virtual bool DeallocPRtspControllerChild(PRtspControllerChild*) MOZ_OVERRIDE;
+  virtual PChannelDiverterChild*
+  AllocPChannelDiverterChild(const ChannelDiverterArgs& channel) MOZ_OVERRIDE;
+  virtual bool
+  DeallocPChannelDiverterChild(PChannelDiverterChild* actor) MOZ_OVERRIDE;
 };
 
 /**
  * Reference to the PNecko Child protocol.
  * Null if this is not a content process.
  */
 extern PNeckoChild *gNeckoChild;
 

--- a/netwerk/ipc/NeckoParent.cpp
+++ b/netwerk/ipc/NeckoParent.cpp
@@ -13,16 +13,17 @@
 #include "mozilla/net/WyciwygChannelParent.h"
 #include "mozilla/net/FTPChannelParent.h"
 #include "mozilla/net/WebSocketChannelParent.h"
 #ifdef NECKO_PROTOCOL_rtsp
 #include "mozilla/net/RtspControllerParent.h"
 #endif
 #include "mozilla/net/DNSRequestParent.h"
 #include "mozilla/net/RemoteOpenFileParent.h"
+#include "mozilla/net/ChannelDiverterParent.h"
 #include "mozilla/dom/ContentParent.h"
 #include "mozilla/dom/TabParent.h"
 #include "mozilla/dom/network/TCPSocketParent.h"
 #include "mozilla/dom/network/TCPServerSocketParent.h"
 #include "mozilla/dom/network/UDPSocketParent.h"
 #include "mozilla/ipc/URIUtils.h"
 #include "mozilla/LoadContext.h"
 #include "mozilla/AppProcessChecker.h"
@@ -603,16 +604,38 @@ bool
 NeckoParent::RecvCancelHTMLDNSPrefetch(const nsString& hostname,
                                  const uint16_t& flags,
                                  const nsresult& reason)
 {
   nsHTMLDNSPrefetch::CancelPrefetch(hostname, flags, reason);
   return true;
 }
 
+PChannelDiverterParent*
+NeckoParent::AllocPChannelDiverterParent(const ChannelDiverterArgs& channel)
+{
+  return new ChannelDiverterParent();
+}
+
+bool
+NeckoParent::RecvPChannelDiverterConstructor(PChannelDiverterParent* actor,
+                                             const ChannelDiverterArgs& channel)
+{
+  auto parent = static_cast<ChannelDiverterParent*>(actor);
+  parent->Init(channel);
+  return true;
+}
+
+bool
+NeckoParent::DeallocPChannelDiverterParent(PChannelDiverterParent* parent)
+{
+  delete static_cast<ChannelDiverterParent*>(parent);
+  return true;
+}
+
 void
 NeckoParent::CloneManagees(ProtocolBase* aSource,
                          mozilla::ipc::ProtocolCloneContext* aCtx)
 {
   aCtx->SetNeckoParent(this); // For cloning protocols managed by this.
   PNeckoParent::CloneManagees(aSource, aCtx);
 }
 

--- a/netwerk/ipc/NeckoParent.h
+++ b/netwerk/ipc/NeckoParent.h
@@ -139,16 +139,24 @@ protected:
                                          const nsresult& reason) MOZ_OVERRIDE;
 
   virtual mozilla::ipc::IProtocol*
   CloneProtocol(Channel* aChannel,
                 mozilla::ipc::ProtocolCloneContext* aCtx) MOZ_OVERRIDE;
   virtual PRtspControllerParent* AllocPRtspControllerParent() MOZ_OVERRIDE;
   virtual bool DeallocPRtspControllerParent(PRtspControllerParent*) MOZ_OVERRIDE;
 
+  virtual PChannelDiverterParent*
+  AllocPChannelDiverterParent(const ChannelDiverterArgs& channel) MOZ_OVERRIDE;
+  virtual bool
+  RecvPChannelDiverterConstructor(PChannelDiverterParent* actor,
+                                  const ChannelDiverterArgs& channel) MOZ_OVERRIDE;
+  virtual bool DeallocPChannelDiverterParent(PChannelDiverterParent* actor)
+                                                                MOZ_OVERRIDE;
+
 private:
   nsCString mCoreAppsBasePath;
   nsCString mWebAppsBasePath;
 };
 
 } // namespace net
 } // namespace mozilla
 

new file mode 100644
--- /dev/null
+++ b/netwerk/ipc/PChannelDiverter.ipdl
@@ -0,0 +1,25 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80 ft=cpp: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+include protocol PFTPChannel;
+include protocol PHttpChannel;
+include protocol PNecko;
+
+namespace mozilla {
+namespace net {
+
+// Used when diverting necko channels from child back to the parent.
+// See nsIDivertableChannel.
+async protocol PChannelDiverter
+{
+  manager PNecko;
+
+child:
+  __delete__();
+};
+
+}// namespace net
+}// namespace mozilla

--- a/netwerk/ipc/PNecko.ipdl
+++ b/netwerk/ipc/PNecko.ipdl
@@ -12,16 +12,17 @@ include protocol PBrowser;
 include protocol PWyciwygChannel;
 include protocol PFTPChannel;
 include protocol PWebSocket;
 include protocol PTCPSocket;
 include protocol PTCPServerSocket;
 include protocol PUDPSocket;
 include protocol PRemoteOpenFile;
 include protocol PDNSRequest;
+include protocol PChannelDiverter;
 include protocol PBlob; //FIXME: bug #792908
 
 include protocol PRtspController;
 include URIParams;
 include InputStreamParams;
 include NeckoChannelParams;
 
 
@@ -40,16 +41,17 @@ sync protocol PNecko
   manages PFTPChannel;
   manages PWebSocket;
   manages PTCPSocket;
   manages PTCPServerSocket;
   manages PUDPSocket;
   manages PDNSRequest;
   manages PRemoteOpenFile;
   manages PRtspController;
+  manages PChannelDiverter;
 
 parent:
   __delete__();
 
   PCookieService();
   PHttpChannel(nullable PBrowser browser,
                SerializedLoadContext loadContext,
                HttpChannelCreationArgs args);
@@ -63,16 +65,17 @@ parent:
 
   PDNSRequest(nsCString hostName, uint32_t flags);
 
   PRemoteOpenFile(URIParams fileuri, OptionalURIParams appuri);
 
   HTMLDNSPrefetch(nsString hostname, uint16_t flags);
   CancelHTMLDNSPrefetch(nsString hostname, uint16_t flags, nsresult reason);
   PRtspController();
+  PChannelDiverter(ChannelDiverterArgs channel);
 
 both:
   PTCPSocket();
 };
 
 
 } // namespace net
 } // namespace mozilla

--- a/netwerk/ipc/moz.build
+++ b/netwerk/ipc/moz.build
@@ -26,16 +26,17 @@ UNIFIED_SOURCES += [
     'NeckoCommon.cpp',
     'NeckoParent.cpp',
     'RemoteOpenFileChild.cpp',
     'RemoteOpenFileParent.cpp',
 ]
 
 IPDL_SOURCES = [
     'NeckoChannelParams.ipdlh',
+    'PChannelDiverter.ipdl',
     'PNecko.ipdl',
     'PRemoteOpenFile.ipdl',
     'PRtspController.ipdl',
 ]
 
 FAIL_ON_WARNINGS = True
 
 include('/ipc/chromium/chromium-config.mozbuild')

--- a/netwerk/protocol/ftp/FTPChannelChild.cpp
+++ b/netwerk/protocol/ftp/FTPChannelChild.cpp
@@ -425,16 +425,28 @@ FTPChannelChild::DoFailedAsyncOpen(const
 
   mListener = nullptr;
   mListenerContext = nullptr;
 
   if (mIPCOpen)
     Send__delete__(this);
 }
 
+bool
+FTPChannelChild::RecvFlushedForDiversion()
+{
+  return false;
+}
+
+bool
+FTPChannelChild::RecvDivertMessages()
+{
+  return false;
+}
+
 class FTPDeleteSelfEvent : public ChannelEvent
 {
  public:
   FTPDeleteSelfEvent(FTPChannelChild* aChild)
   : mChild(aChild) {}
   void Run() { mChild->DoDeleteSelf(); }
  private:
   FTPChannelChild* mChild;

--- a/netwerk/protocol/ftp/FTPChannelChild.h
+++ b/netwerk/protocol/ftp/FTPChannelChild.h
@@ -74,16 +74,18 @@ protected:
                           const PRTime& aLastModified,
                           const nsCString& aEntityID,
                           const URIParams& aURI) MOZ_OVERRIDE;
   bool RecvOnDataAvailable(const nsCString& data,
                            const uint64_t& offset,
                            const uint32_t& count) MOZ_OVERRIDE;
   bool RecvOnStopRequest(const nsresult& statusCode) MOZ_OVERRIDE;
   bool RecvFailedAsyncOpen(const nsresult& statusCode) MOZ_OVERRIDE;
+  bool RecvFlushedForDiversion() MOZ_OVERRIDE;
+  bool RecvDivertMessages() MOZ_OVERRIDE;
   bool RecvDeleteSelf() MOZ_OVERRIDE;
 
   void DoOnStartRequest(const int64_t& aContentLength,
                         const nsCString& aContentType,
                         const PRTime& aLastModified,
                         const nsCString& aEntityID,
                         const URIParams& aURI);
   void DoOnDataAvailable(const nsCString& data,

--- a/netwerk/protocol/ftp/FTPChannelParent.cpp
+++ b/netwerk/protocol/ftp/FTPChannelParent.cpp
@@ -174,16 +174,36 @@ FTPChannelParent::RecvSuspend()
 bool
 FTPChannelParent::RecvResume()
 {
   if (mChannel)
     mChannel->Resume();
   return true;
 }
 
+bool
+FTPChannelParent::RecvDivertOnDataAvailable(const nsCString& data,
+                                            const uint64_t& offset,
+                                            const uint32_t& count)
+{
+  return false;
+}
+
+bool
+FTPChannelParent::RecvDivertOnStopRequest(const nsresult& statusCode)
+{
+  return false;
+}
+
+bool
+FTPChannelParent::RecvDivertComplete()
+{
+  return false;
+}
+
 //-----------------------------------------------------------------------------
 // FTPChannelParent::nsIRequestObserver
 //-----------------------------------------------------------------------------
 
 NS_IMETHODIMP
 FTPChannelParent::OnStartRequest(nsIRequest* aRequest, nsISupports* aContext)
 {
   LOG(("FTPChannelParent::OnStartRequest [this=%p]\n", this));

--- a/netwerk/protocol/ftp/FTPChannelParent.h
+++ b/netwerk/protocol/ftp/FTPChannelParent.h
@@ -42,16 +42,21 @@ protected:
 
   // used to connect redirected-to channel in parent with just created
   // ChildChannel.  Used during HTTP->FTP redirects.
   bool ConnectChannel(const uint32_t& channelId);
 
   virtual bool RecvCancel(const nsresult& status) MOZ_OVERRIDE;
   virtual bool RecvSuspend() MOZ_OVERRIDE;
   virtual bool RecvResume() MOZ_OVERRIDE;
+  virtual bool RecvDivertOnDataAvailable(const nsCString& data,
+                                         const uint64_t& offset,
+                                         const uint32_t& count) MOZ_OVERRIDE;
+  virtual bool RecvDivertOnStopRequest(const nsresult& statusCode) MOZ_OVERRIDE;
+  virtual bool RecvDivertComplete() MOZ_OVERRIDE;
 
   virtual void ActorDestroy(ActorDestroyReason why) MOZ_OVERRIDE;
 
   nsRefPtr<nsFtpChannel> mChannel;
 
   bool mIPCClosed;
 
   nsCOMPtr<nsILoadContext> mLoadContext;

--- a/netwerk/protocol/ftp/PFTPChannel.ipdl
+++ b/netwerk/protocol/ftp/PFTPChannel.ipdl
@@ -27,20 +27,39 @@ parent:
   // see PNecko.ipdl
 
   __delete__();
 
   Cancel(nsresult status);
   Suspend();
   Resume();
 
+  // Divert OnDataAvailable to the parent.
+  DivertOnDataAvailable(nsCString data,
+                        uint64_t  offset,
+                        uint32_t  count);
+
+  // Divert OnStopRequest to the parent.
+  DivertOnStopRequest(nsresult statusCode);
+
+  // Child has no more events/messages to divert to the parent.
+  DivertComplete();
+
 child:
   OnStartRequest(int64_t aContentLength, nsCString aContentType,
                  PRTime aLastModified, nsCString aEntityID, URIParams aURI);
   OnDataAvailable(nsCString data, uint64_t offset, uint32_t count);
   OnStopRequest(nsresult statusCode);
   FailedAsyncOpen(nsresult statusCode);
+
+  // Parent has been suspended for diversion; no more events to be enqueued.
+  FlushedForDiversion();
+
+  // Child should resume processing the ChannelEventQueue, i.e. diverting any
+  // OnDataAvailable and OnStopRequest messages in the queue back to the parent.
+  DivertMessages();
+
   DeleteSelf();
 };
 
 } // namespace net
 } // namespace mozilla
 

--- a/netwerk/protocol/http/HttpChannelChild.cpp
+++ b/netwerk/protocol/http/HttpChannelChild.cpp
@@ -772,16 +772,28 @@ HttpChannelChild::RecvRedirect3Complete(
   if (mEventQ->ShouldEnqueue()) {
     mEventQ->Enqueue(new Redirect3Event(this));
   } else {
     Redirect3Complete();
   }
   return true;
 }
 
+bool
+HttpChannelChild::RecvFlushedForDiversion()
+{
+  return false;
+}
+
+bool
+HttpChannelChild::RecvDivertMessages()
+{
+  return false;
+}
+
 void
 HttpChannelChild::Redirect3Complete()
 {
   nsresult rv = NS_OK;
 
   // Chrome channel has been AsyncOpen'd.  Reflect this in child.
   if (mRedirectChannelChild)
     rv = mRedirectChannelChild->CompleteRedirectSetup(mListener,

--- a/netwerk/protocol/http/HttpChannelChild.h
+++ b/netwerk/protocol/http/HttpChannelChild.h
@@ -113,16 +113,18 @@ protected:
   bool RecvFailedAsyncOpen(const nsresult& status) MOZ_OVERRIDE;
   bool RecvRedirect1Begin(const uint32_t& newChannel,
                           const URIParams& newURI,
                           const uint32_t& redirectFlags,
                           const nsHttpResponseHead& responseHead) MOZ_OVERRIDE;
   bool RecvRedirect3Complete() MOZ_OVERRIDE;
   bool RecvAssociateApplicationCache(const nsCString& groupID,
                                      const nsCString& clientID) MOZ_OVERRIDE;
+  bool RecvFlushedForDiversion() MOZ_OVERRIDE;
+  bool RecvDivertMessages() MOZ_OVERRIDE;
   bool RecvDeleteSelf() MOZ_OVERRIDE;
 
   bool GetAssociatedContentSecurity(nsIAssociatedContentSecurity** res = nullptr);
   virtual void DoNotifyListenerCleanup();
 
 private:
   RequestHeaderTuples mClientSetRequestHeaders;
   nsCOMPtr<nsIChildChannel> mRedirectChannelChild;

--- a/netwerk/protocol/http/HttpChannelParent.cpp
+++ b/netwerk/protocol/http/HttpChannelParent.cpp
@@ -430,16 +430,36 @@ HttpChannelParent::RecvMarkOfflineCacheE
   if (mOfflineForeignMarker) {
     mOfflineForeignMarker->MarkAsForeign();
     mOfflineForeignMarker = 0;
   }
 
   return true;
 }
 
+bool
+HttpChannelParent::RecvDivertOnDataAvailable(const nsCString& data,
+                                             const uint64_t& offset,
+                                             const uint32_t& count)
+{
+  return false;
+}
+
+bool
+HttpChannelParent::RecvDivertOnStopRequest(const nsresult& statusCode)
+{
+  return false;
+}
+
+bool
+HttpChannelParent::RecvDivertComplete()
+{
+  return false;
+}
+
 //-----------------------------------------------------------------------------
 // HttpChannelParent::nsIRequestObserver
 //-----------------------------------------------------------------------------
 
 NS_IMETHODIMP
 HttpChannelParent::OnStartRequest(nsIRequest *aRequest, nsISupports *aContext)
 {
   LOG(("HttpChannelParent::OnStartRequest [this=%p]\n", this));

--- a/netwerk/protocol/http/HttpChannelParent.h
+++ b/netwerk/protocol/http/HttpChannelParent.h
@@ -84,17 +84,21 @@ protected:
   virtual bool RecvCancel(const nsresult& status) MOZ_OVERRIDE;
   virtual bool RecvRedirect2Verify(const nsresult& result,
                                    const RequestHeaderTuples& changedHeaders,
                                    const OptionalURIParams& apiRedirectUri) MOZ_OVERRIDE;
   virtual bool RecvUpdateAssociatedContentSecurity(const int32_t& broken,
                                                    const int32_t& no) MOZ_OVERRIDE;
   virtual bool RecvDocumentChannelCleanup() MOZ_OVERRIDE;
   virtual bool RecvMarkOfflineCacheEntryAsForeign() MOZ_OVERRIDE;
-
+  virtual bool RecvDivertOnDataAvailable(const nsCString& data,
+                                         const uint64_t& offset,
+                                         const uint32_t& count) MOZ_OVERRIDE;
+  virtual bool RecvDivertOnStopRequest(const nsresult& statusCode) MOZ_OVERRIDE;
+  virtual bool RecvDivertComplete() MOZ_OVERRIDE;
   virtual void ActorDestroy(ActorDestroyReason why) MOZ_OVERRIDE;
 
 protected:
   friend class HttpChannelParentListener;
   nsRefPtr<mozilla::dom::TabParent> mTabParent;
 
 private:
   nsCOMPtr<nsIChannel>                    mChannel;

--- a/netwerk/protocol/http/PHttpChannel.ipdl
+++ b/netwerk/protocol/http/PHttpChannel.ipdl
@@ -61,16 +61,27 @@ parent:
   // load this document from the offline cache group it was just loaded from.
   // Marking the cache entry as foreign in its cache group will prevent
   // the document to load from the bad offline cache group. After it is marked,
   // we reload the document to take the effect. If we fail to mark the entry
   // as foreign, we will end up in the same situation and reload again and
   // again, indefinitely.
   MarkOfflineCacheEntryAsForeign();
 
+  // Divert OnDataAvailable to the parent.
+  DivertOnDataAvailable(nsCString data,
+                        uint64_t  offset,
+                        uint32_t  count);
+
+  // Divert OnStopRequest to the parent.
+  DivertOnStopRequest(nsresult statusCode);
+
+  // Child has no more events/messages to divert to the parent.
+  DivertComplete();
+
   __delete__();
 
 child:
   OnStartRequest(nsHttpResponseHead  responseHead,
                  bool                useResponseHead,
                  nsHttpHeaderArray   requestHeaders,
                  bool                isFromCache,
                  bool                cacheEntryAvailable,
@@ -108,16 +119,23 @@ child:
 
   // Called if redirect successful so that child can complete setup.
   Redirect3Complete();
 
   // Associte the child with an application ids
   AssociateApplicationCache(nsCString groupID,
                             nsCString clientID);
 
+  // Parent has been suspended for diversion; no more events to be enqueued.
+  FlushedForDiversion();
+
+  // Child should resume processing the ChannelEventQueue, i.e. diverting any
+  // OnDataAvailable and OnStopRequest messages in the queue back to the parent.
+  DivertMessages();
+
   // Tell child to delete channel (all IPDL deletes must be done from child to
   // avoid races: see bug 591708).
   DeleteSelf();
 };
 
 
 } // namespace net
 } // namespace mozilla