Bug 1575744 - P2. Add nsIProcessSwitchRequestor interface. r=mayhemer,nika

Will allow for SessionStore.jsm process switching to be used by other objects than nsHttpChannel.

Differential Revision: https://phabricator.services.mozilla.com/D46015

--HG--
extra : moz-landing-system : lando

browser/components/sessionstore/SessionStore.jsm

@@ -2606,8 +2606,8 @@ var SessionStoreInternal = {
   },
 
   // Examine the channel response to see if we should change the process
-  // performing the given load.
-  onMayChangeProcess(aChannel) {
+  // performing the given load. aRequestor implements nsIProcessSwitchRequestor
+  onMayChangeProcess(aRequestor) {
     if (
       !E10SUtils.useHttpResponseProcessSelection() &&
       !E10SUtils.useCrossOriginOpenerPolicy()
@@ -2615,19 +2615,26 @@ var SessionStoreInternal = {
       return;
     }
 
-    aChannel.QueryInterface(Ci.nsIHttpChannel);
+    let switchRequestor;
+    try {
+      switchRequestor = aRequestor.QueryInterface(Ci.nsIProcessSwitchRequestor);
+    } catch (e) {
+      debug(`[process-switch]: object not compatible with process switching `);
+      return;
+    }
 
-    if (!aChannel.isDocument || !aChannel.loadInfo) {
+    const channel = switchRequestor.channel;
+    if (!channel.isDocument || !channel.loadInfo) {
       return; // Not a document load.
     }
 
     // Check that the document has a corresponding BrowsingContext.
     let browsingContext;
-    let cp = aChannel.loadInfo.externalContentPolicyType;
+    let cp = channel.loadInfo.externalContentPolicyType;
     if (cp == Ci.nsIContentPolicy.TYPE_DOCUMENT) {
-      browsingContext = aChannel.loadInfo.browsingContext;
+      browsingContext = channel.loadInfo.browsingContext;
     } else {
-      browsingContext = aChannel.loadInfo.frameBrowsingContext;
+      browsingContext = channel.loadInfo.frameBrowsingContext;
     }
 
     if (!browsingContext) {
@@ -2691,7 +2698,7 @@ var SessionStoreInternal = {
 
     // Determine the process type the load should be performed in.
     let resultPrincipal = Services.scriptSecurityManager.getChannelResultPrincipal(
-      aChannel
+      channel
     );
     let remoteType = E10SUtils.getRemoteTypeForPrincipal(
       resultPrincipal,
@@ -2703,7 +2710,7 @@ var SessionStoreInternal = {
     if (
       currentRemoteType == remoteType &&
       (!E10SUtils.useCrossOriginOpenerPolicy() ||
-        !aChannel.hasCrossOriginOpenerPolicyMismatch())
+        !switchRequestor.hasCrossOriginOpenerPolicyMismatch())
     ) {
       debug(`[process-switch]: type (${remoteType}) is compatible - ignoring`);
       return;
@@ -2719,7 +2726,7 @@ var SessionStoreInternal = {
 
     const isCOOPSwitch =
       E10SUtils.useCrossOriginOpenerPolicy() &&
-      aChannel.hasCrossOriginOpenerPolicyMismatch();
+      switchRequestor.hasCrossOriginOpenerPolicyMismatch();
 
     // ------------------------------------------------------------------------
     // DANGER ZONE: Perform a process switch into the new process. This is
@@ -2729,11 +2736,11 @@ var SessionStoreInternal = {
     let tabPromise = this._doProcessSwitch(
       browsingContext,
       remoteType,
-      aChannel,
+      channel,
       identifier,
       isCOOPSwitch
     );
-    aChannel.switchProcessTo(tabPromise, identifier);
+    switchRequestor.switchProcessTo(tabPromise, identifier);
   },
 
   /* ........ nsISessionStore API .............. */

netwerk/base/nsICrossProcessSwitchChannel.idl

@@ -37,3 +37,41 @@ interface nsICrossProcessSwitchChannel : nsISupports
    */
   void triggerCrossProcessSwitch(in nsIHttpChannel channel, in uint64_t identifier);
 };
+
+/**
+ * The nsIProcessSwitchRequestor interface allows clients to instruct
+ * SessionStore.jsm that a channel setup has completed and a process switch
+ * may be required. This works alongside the on-may-change-process observer
+ * notification.
+ * This interface must be used only from the XPCOM main thread.
+ */
+[scriptable, uuid(fce8497b-c57c-4557-b360-3efefc83eff5)]
+interface nsIProcessSwitchRequestor : nsISupports
+{
+  /**
+   * The underlying channel object that was intercepted and that could trigger
+   * a process.
+   */
+  readonly attribute nsIChannel channel;
+
+  /**
+   * Instructs the callee to be loaded in a new process. Like 'redirectTo'
+   * this can only be used on channels that have not yet called their
+   * listener's OnStartRequest(). Can only be called during the
+   * http-on-may-change-process observer notification.
+   *
+   * @param aTabPromise   a promise which resolves to a nsIRemotTab object
+   *                      which the load will proceed in.
+   * @param aIdentifier   a 64-bit ID which will be provided to the
+   *                      ChildProcessChannelListener.
+   */
+  [must_use] void switchProcessTo(in Promise aTabPromise,
+                                  in unsigned long long aIdentifier);
+
+  /**
+   * Used to determine if there is a Cross-Origin-Opener-Policy mismatch
+   * that would require switching the channel to another process.
+   * @throws NS_ERROR_NOT_AVAILABLE if we don't have a responseHead
+   */
+  [must_use] boolean hasCrossOriginOpenerPolicyMismatch();
+};

netwerk/protocol/http/HttpBaseChannel.cpp

@@ -1926,17 +1926,6 @@ HttpBaseChannel::RedirectTo(nsIURI* targetURI) {
   return NS_OK;
 }
 
-NS_IMETHODIMP
-HttpBaseChannel::SwitchProcessTo(mozilla::dom::Promise* aBrowserParent,
-                                 uint64_t aIdentifier) {
-  return NS_ERROR_NOT_AVAILABLE;
-}
-
-NS_IMETHODIMP
-HttpBaseChannel::HasCrossOriginOpenerPolicyMismatch(bool* aMismatch) {
-  return NS_ERROR_NOT_AVAILABLE;
-}
-
 NS_IMETHODIMP
 HttpBaseChannel::UpgradeToSecure() {
   // Upgrades are handled internally between http-on-modify-request and

netwerk/protocol/http/HttpBaseChannel.h

@@ -219,9 +219,6 @@ class HttpBaseChannel : public nsHashPropertyBag,
   NS_IMETHOD GetResponseStatusText(nsACString& aValue) override;
   NS_IMETHOD GetRequestSucceeded(bool* aValue) override;
   NS_IMETHOD RedirectTo(nsIURI* newURI) override;
-  NS_IMETHOD SwitchProcessTo(mozilla::dom::Promise* aBrowserParent,
-                             uint64_t aIdentifier) override;
-  NS_IMETHOD HasCrossOriginOpenerPolicyMismatch(bool* aMismatch) override;
   NS_IMETHOD UpgradeToSecure() override;
   NS_IMETHOD GetRequestContextID(uint64_t* aRCID) override;
   NS_IMETHOD GetTransferSize(uint64_t* aTransferSize) override;

netwerk/protocol/http/NullHttpChannel.cpp

@@ -273,17 +273,6 @@ NullHttpChannel::RedirectTo(nsIURI* aNewURI) {
   return NS_ERROR_NOT_IMPLEMENTED;
 }
 
-NS_IMETHODIMP
-NullHttpChannel::SwitchProcessTo(mozilla::dom::Promise* aBrowserParent,
-                                 uint64_t aIdentifier) {
-  return NS_ERROR_NOT_AVAILABLE;
-}
-
-NS_IMETHODIMP
-NullHttpChannel::HasCrossOriginOpenerPolicyMismatch(bool* aMismatch) {
-  return NS_ERROR_NOT_AVAILABLE;
-}
-
 NS_IMETHODIMP
 NullHttpChannel::UpgradeToSecure() { return NS_ERROR_NOT_IMPLEMENTED; }
 

netwerk/protocol/http/nsHttpChannel.cpp

@@ -6139,6 +6139,7 @@ NS_INTERFACE_MAP_BEGIN(nsHttpChannel)
   NS_INTERFACE_MAP_ENTRY(nsITimerCallback)
   NS_INTERFACE_MAP_ENTRY(nsIChannelWithDivertableParentListener)
   NS_INTERFACE_MAP_ENTRY(nsIRequestTailUnblockCallback)
+  NS_INTERFACE_MAP_ENTRY(nsIProcessSwitchRequestor)
   NS_INTERFACE_MAP_ENTRY_CONCRETE(nsHttpChannel)
 NS_INTERFACE_MAP_END_INHERITING(HttpBaseChannel)
 
@@ -7285,6 +7286,15 @@ class DomPromiseListener final : dom::PromiseNativeHandler {
 
 NS_IMPL_ISUPPORTS0(DomPromiseListener)
 
+//-----------------------------------------------------------------------------
+// nsHttpChannel::nsIProcessSwitchRequestor
+//-----------------------------------------------------------------------------
+
+NS_IMETHODIMP nsHttpChannel::GetChannel(nsIChannel** aChannel) {
+  *aChannel = do_AddRef(this).take();
+  return NS_OK;
+}
+
 NS_IMETHODIMP nsHttpChannel::SwitchProcessTo(
     dom::Promise* aContentProcessIdPromise, uint64_t aIdentifier) {
   MOZ_ASSERT(NS_IsMainThread());
@@ -7310,6 +7320,19 @@ NS_IMETHODIMP nsHttpChannel::SwitchProcessTo(
   return NS_OK;
 }
 
+// This method returns the cached result of running the Cross-Origin-Opener
+// policy compare algorithm by calling ComputeCrossOriginOpenerPolicyMismatch
+NS_IMETHODIMP
+nsHttpChannel::HasCrossOriginOpenerPolicyMismatch(bool* aMismatch) {
+  MOZ_ASSERT(aMismatch);
+  if (!aMismatch) {
+    return NS_ERROR_INVALID_ARG;
+  }
+
+  *aMismatch = mHasCrossOriginOpenerPolicyMismatch;
+  return NS_OK;
+}
+
 nsresult nsHttpChannel::StartCrossProcessRedirect() {
   nsresult rv;
 
@@ -7373,19 +7396,6 @@ static bool CompareCrossOriginOpenerPolicies(
   return false;
 }
 
-// This method returns the cached result of running the Cross-Origin-Opener
-// policy compare algorithm by calling ComputeCrossOriginOpenerPolicyMismatch
-NS_IMETHODIMP
-nsHttpChannel::HasCrossOriginOpenerPolicyMismatch(bool* aMismatch) {
-  MOZ_ASSERT(aMismatch);
-  if (!aMismatch) {
-    return NS_ERROR_INVALID_ARG;
-  }
-
-  *aMismatch = mHasCrossOriginOpenerPolicyMismatch;
-  return NS_OK;
-}
-
 // This runs steps 1-5 of the algorithm when navigating a top level document.
 // See https://gist.github.com/annevk/6f2dd8c79c77123f39797f6bdac43f3e
 nsresult nsHttpChannel::ComputeCrossOriginOpenerPolicyMismatch() {

netwerk/protocol/http/nsHttpChannel.h

@@ -34,6 +34,7 @@
 #include "mozilla/extensions/PStreamFilterParent.h"
 #include "mozilla/Mutex.h"
 #include "nsIRemoteTab.h"
+#include "nsICrossProcessSwitchChannel.h"
 
 class nsDNSPrefetch;
 class nsICancelable;
@@ -78,7 +79,8 @@ class nsHttpChannel final : public HttpBaseChannel,
                             public nsIChannelWithDivertableParentListener,
                             public nsIRaceCacheWithNetwork,
                             public nsIRequestTailUnblockCallback,
-                            public nsITimerCallback {
+                            public nsITimerCallback,
+                            public nsIProcessSwitchRequestor {
  public:
   NS_DECL_ISUPPORTS_INHERITED
   NS_DECL_NSIREQUESTOBSERVER
@@ -100,6 +102,7 @@ class nsHttpChannel final : public HttpBaseChannel,
   NS_DECL_NSIRACECACHEWITHNETWORK
   NS_DECL_NSITIMERCALLBACK
   NS_DECL_NSIREQUESTTAILUNBLOCKCALLBACK
+  NS_DECL_NSIPROCESSSWITCHREQUESTOR
 
   // nsIHttpAuthenticableChannel. We can't use
   // NS_DECL_NSIHTTPAUTHENTICABLECHANNEL because it duplicates cancel() and
@@ -150,9 +153,6 @@ class nsHttpChannel final : public HttpBaseChannel,
   NS_IMETHOD AsyncOpen(nsIStreamListener* aListener) override;
   // nsIHttpChannel
   NS_IMETHOD GetEncodedBodySize(uint64_t* aEncodedBodySize) override;
-  NS_IMETHOD SwitchProcessTo(mozilla::dom::Promise* aBrowserParent,
-                             uint64_t aIdentifier) override;
-  NS_IMETHOD HasCrossOriginOpenerPolicyMismatch(bool* aMismatch) override;
   // nsIHttpChannelInternal
   NS_IMETHOD SetupFallbackChannel(const char* aFallbackKey) override;
   NS_IMETHOD SetChannelIsForDownload(bool aChannelIsForDownload) override;

netwerk/protocol/http/nsHttpHandler.cpp

@@ -15,6 +15,7 @@
 #include "nsHttpChannel.h"
 #include "nsHttpAuthCache.h"
 #include "nsStandardURL.h"
+#include "nsICrossProcessSwitchChannel.h"
 #include "nsIDOMWindow.h"
 #include "nsIHttpChannel.h"
 #include "nsIStandardURL.h"
@@ -806,6 +807,14 @@ void nsHttpHandler::NotifyObservers(nsIChannel* chan, const char* event) {
   if (obsService) obsService->NotifyObservers(chan, event, nullptr);
 }
 
+void nsHttpHandler::NotifyObservers(nsIProcessSwitchRequestor* request,
+                                    const char* event) {
+  LOG(("nsHttpHandler::NotifyObservers [request=%p event=\"%s\"]\n", request,
+       event));
+  nsCOMPtr<nsIObserverService> obsService = services::GetObserverService();
+  if (obsService) obsService->NotifyObservers(request, event, nullptr);
+}
+
 nsresult nsHttpHandler::AsyncOnChannelRedirect(
     nsIChannel* oldChan, nsIChannel* newChan, uint32_t flags,
     nsIEventTarget* mainThreadEventTarget) {

netwerk/protocol/http/nsHttpHandler.h

@@ -29,6 +29,7 @@ class nsIHttpChannel;
 class nsIPrefBranch;
 class nsICancelable;
 class nsICookieService;
+class nsIProcessSwitchRequestor;
 class nsIIOService;
 class nsIRequestContextService;
 class nsISiteSecurityService;
@@ -407,8 +408,8 @@ class nsHttpHandler final : public nsIHttpProtocolHandler,
     NotifyObservers(chan, NS_HTTP_ON_EXAMINE_CACHED_RESPONSE_TOPIC);
   }
 
-  void OnMayChangeProcess(nsIHttpChannel* chan) {
-    NotifyObservers(chan, NS_HTTP_ON_MAY_CHANGE_PROCESS_TOPIC);
+  void OnMayChangeProcess(nsIProcessSwitchRequestor* request) {
+    NotifyObservers(request, NS_HTTP_ON_MAY_CHANGE_PROCESS_TOPIC);
   }
 
   // Generates the host:port string for use in the Host: header as well as the
@@ -479,6 +480,7 @@ class nsHttpHandler final : public nsIHttpProtocolHandler,
   MOZ_MUST_USE nsresult InitConnectionMgr();
 
   void NotifyObservers(nsIChannel* chan, const char* event);
+  void NotifyObservers(nsIProcessSwitchRequestor* request, const char* event);
 
   void SetFastOpenOSSupport();
 

netwerk/protocol/http/nsIHttpChannel.idl

@@ -415,26 +415,6 @@ interface nsIHttpChannel : nsIIdentChannel
      */
     [must_use] void redirectTo(in nsIURI aTargetURI);
 
-    /**
-     * Instructs the channel to be loaded in a new process. Like 'redirectTo'
-     * this can only be used on channels that have not yet called their
-     * listener's OnStartRequest().
-     *
-     * @param aTabPromise   a promise which resolves to a nsIRemotTab object
-     *                      which the load will proceed in.
-     * @param aIdentifier   a 64-bit ID which will be provided to the
-     *                      ChildProcessChannelListener.
-     */
-    [must_use] void switchProcessTo(in Promise aTabPromise,
-                                    in unsigned long long aIdentifier);
-
-    /**
-     * Used to determine if there is a Cross-Origin-Opener-Policy mismatch
-     * that would require switching the channel to another process.
-     * @throws NS_ERROR_NOT_AVAILABLE if we don't have a responseHead
-     */
-    [must_use] boolean hasCrossOriginOpenerPolicyMismatch();
-
     /**
      * Flags a channel to be upgraded to HTTPS.
      *

netwerk/protocol/http/nsIHttpProtocolHandler.idl

@@ -175,9 +175,9 @@ interface nsIHttpProtocolHandler : nsIProxiedProtocolHandler
 
 /**
  * The observer of this topic is notified before before the response for a HTTP
- * load is available. The "subject" of the notification is the nsIHttpChannel
- * instance. Observers may call "switchProcessTo" to perform a process switch
- * while this is being run.
+ * load is available. The "subject" of the notification is the
+ * nsIProcessSwitchRequestor instance. Observers may call "switchProcessTo" to
+ * perform a process switch while this is being run.
  */
 #define NS_HTTP_ON_MAY_CHANGE_PROCESS_TOPIC "http-on-may-change-process"
 

netwerk/protocol/viewsource/moz.build

@@ -22,6 +22,8 @@ EXPORTS += [
 FINAL_LIBRARY = 'xul'
 LOCAL_INCLUDES += [
     '/netwerk/base',
+    # For nsHttpChannel.h
+    '/netwerk/protocol/http',
 ]
 
 include('/ipc/chromium/chromium-config.mozbuild')

netwerk/protocol/viewsource/nsViewSourceChannel.cpp

@@ -5,17 +5,18 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 #include "nsViewSourceChannel.h"
-#include "nsIIOService.h"
-#include "nsMimeTypes.h"
-#include "nsNetUtil.h"
-#include "nsContentUtils.h"
-#include "nsIHttpHeaderVisitor.h"
-#include "nsContentSecurityManager.h"
-#include "nsServiceManagerUtils.h"
-#include "nsIInputStreamChannel.h"
 #include "mozilla/DebugOnly.h"
 #include "mozilla/NullPrincipal.h"
+#include "nsContentSecurityManager.h"
+#include "nsContentUtils.h"
+#include "nsHttpChannel.h"
+#include "nsIHttpHeaderVisitor.h"
+#include "nsIIOService.h"
+#include "nsIInputStreamChannel.h"
 #include "nsIReferrerInfo.h"
+#include "nsMimeTypes.h"
+#include "nsNetUtil.h"
+#include "nsServiceManagerUtils.h"
 
 NS_IMPL_ADDREF(nsViewSourceChannel)
 NS_IMPL_RELEASE(nsViewSourceChannel)
@@ -40,6 +41,8 @@ NS_INTERFACE_MAP_BEGIN(nsViewSourceChannel)
   NS_INTERFACE_MAP_ENTRY_AMBIGUOUS(nsIRequest, nsIViewSourceChannel)
   NS_INTERFACE_MAP_ENTRY_AMBIGUOUS(nsIChannel, nsIViewSourceChannel)
   NS_INTERFACE_MAP_ENTRY_AMBIGUOUS(nsISupports, nsIViewSourceChannel)
+  NS_INTERFACE_MAP_ENTRY_CONDITIONAL(nsIProcessSwitchRequestor,
+                                     IsNsHttpChannel())
 NS_INTERFACE_MAP_END
 
 nsresult nsViewSourceChannel::Init(nsIURI* uri, nsILoadInfo* aLoadInfo) {
@@ -942,24 +945,6 @@ nsViewSourceChannel::RedirectTo(nsIURI* uri) {
   return !mHttpChannel ? NS_ERROR_NULL_POINTER : mHttpChannel->RedirectTo(uri);
 }
 
-NS_IMETHODIMP
-nsViewSourceChannel::SwitchProcessTo(mozilla::dom::Promise* aBrowserParent,
-                                     uint64_t aIdentifier) {
-  return !mHttpChannel
-             ? NS_ERROR_NULL_POINTER
-             : mHttpChannel->SwitchProcessTo(aBrowserParent, aIdentifier);
-}
-
-NS_IMETHODIMP
-nsViewSourceChannel::HasCrossOriginOpenerPolicyMismatch(bool* aMismatch) {
-  MOZ_ASSERT(aMismatch);
-  if (!aMismatch) {
-    return NS_ERROR_INVALID_ARG;
-  }
-  *aMismatch = false;
-  return NS_OK;
-}
-
 NS_IMETHODIMP
 nsViewSourceChannel::UpgradeToSecure() {
   return !mHttpChannel ? NS_ERROR_NULL_POINTER
@@ -1057,3 +1042,49 @@ void nsViewSourceChannel::SetHasSandboxedAuxiliaryNavigations(
         aHasSandboxedAuxiliaryNavigations);
   }
 }
+
+//-----------------------------------------------------------------------------
+// nsViewSourceChannel::nsIProcessSwitchRequestor
+//-----------------------------------------------------------------------------
+
+NS_IMETHODIMP nsViewSourceChannel::GetChannel(nsIChannel** aChannel) {
+  if (!IsNsHttpChannel()) {
+    return NS_ERROR_NOT_AVAILABLE;
+  }
+  *aChannel = mHttpChannel;
+  NS_ADDREF(*aChannel);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsViewSourceChannel::SwitchProcessTo(mozilla::dom::Promise* aBrowserParent,
+                                     uint64_t aIdentifier) {
+  if (!IsNsHttpChannel()) {
+    return NS_ERROR_NOT_AVAILABLE;
+  }
+  nsCOMPtr<mozilla::net::nsHttpChannel> httpChannel =
+      do_QueryInterface(mHttpChannel);
+  return httpChannel->SwitchProcessTo(aBrowserParent, aIdentifier);
+}
+
+NS_IMETHODIMP
+nsViewSourceChannel::HasCrossOriginOpenerPolicyMismatch(bool* aMismatch) {
+  if (!IsNsHttpChannel()) {
+    return NS_ERROR_NOT_AVAILABLE;
+  }
+  MOZ_ASSERT(aMismatch);
+  if (!aMismatch) {
+    return NS_ERROR_INVALID_ARG;
+  }
+  *aMismatch = false;
+  return NS_OK;
+}
+
+bool nsViewSourceChannel::IsNsHttpChannel() const {
+  if (!mHttpChannel) {
+    return false;
+  }
+  nsCOMPtr<mozilla::net::nsHttpChannel> httpChannel =
+      do_QueryInterface(mHttpChannel);
+  return !!httpChannel;
+}

netwerk/protocol/viewsource/nsViewSourceChannel.h

@@ -6,18 +6,19 @@
 #ifndef nsViewSourceChannel_h___
 #define nsViewSourceChannel_h___
 
-#include "nsString.h"
-#include "nsCOMPtr.h"
-#include "nsIViewSourceChannel.h"
-#include "nsIURI.h"
-#include "nsIStreamListener.h"
-#include "nsIHttpChannel.h"
-#include "nsIHttpChannelInternal.h"
-#include "nsICachingChannel.h"
-#include "nsIApplicationCacheChannel.h"
-#include "nsIFormPOSTActionChannel.h"
 #include "mozilla/Attributes.h"
 #include "mozilla/net/NeckoChannelParams.h"
+#include "nsCOMPtr.h"
+#include "nsIApplicationCacheChannel.h"
+#include "nsICachingChannel.h"
+#include "nsICrossProcessSwitchChannel.h"
+#include "nsIFormPOSTActionChannel.h"
+#include "nsIHttpChannel.h"
+#include "nsIHttpChannelInternal.h"
+#include "nsIStreamListener.h"
+#include "nsIURI.h"
+#include "nsIViewSourceChannel.h"
+#include "nsString.h"
 
 class nsViewSourceChannel final : public nsIViewSourceChannel,
                                   public nsIStreamListener,
@@ -25,7 +26,8 @@ class nsViewSourceChannel final : public nsIViewSourceChannel,
                                   public nsIHttpChannelInternal,
                                   public nsICachingChannel,
                                   public nsIApplicationCacheChannel,
-                                  public nsIFormPOSTActionChannel {
+                                  public nsIFormPOSTActionChannel,
+                                  public nsIProcessSwitchRequestor {
  public:
   NS_DECL_ISUPPORTS
   NS_DECL_NSIREQUEST
@@ -35,6 +37,7 @@ class nsViewSourceChannel final : public nsIViewSourceChannel,
   NS_DECL_NSISTREAMLISTENER
   NS_DECL_NSIREQUESTOBSERVER
   NS_DECL_NSIHTTPCHANNEL
+  NS_DECL_NSIPROCESSSWITCHREQUESTOR
   NS_FORWARD_SAFE_NSICACHEINFOCHANNEL(mCacheInfoChannel)
   NS_FORWARD_SAFE_NSICACHINGCHANNEL(mCachingChannel)
   NS_FORWARD_SAFE_NSIAPPLICATIONCACHECHANNEL(mApplicationCacheChannel)
@@ -82,6 +85,9 @@ class nsViewSourceChannel final : public nsIViewSourceChannel,
   bool mIsDocument;  // keeps track of the LOAD_DOCUMENT_URI flag
   bool mOpened;
   bool mIsSrcdocChannel;
+
+ private:
+  bool IsNsHttpChannel() const;
 };
 
 #endif /* nsViewSourceChannel_h___ */

netwerk/test/browser/browser_cross_process_redirect.js

@@ -40,26 +40,28 @@ ProcessChooser.prototype = {
     Services.obs.removeObserver(this, "http-on-may-change-process");
   },
 
-  examine(aChannel) {
-    if (this.channel && this.channel != aChannel) {
+  examine(aRequestor) {
+    const channel = aRequestor.channel;
+
+    if (this.channel && this.channel != channel) {
       // Hack: this is just so we don't get redirected multiple times.
       info("same channel. give null");
       return;
     }
 
-    if (aChannel.URI.host != this.toDomain) {
-      info("wrong host for channel " + aChannel.URI.host);
+    if (channel.URI.host != this.toDomain) {
+      info("wrong host for channel " + channel.URI.host);
       return;
     }
 
-    let redirects = aChannel.loadInfo.redirectChain;
+    let redirects = channel.loadInfo.redirectChain;
     if (redirects[redirects.length - 1].principal.URI.host != this.fromDomain) {
       info("didn't find redirect");
       return;
     }
 
     info("setting channel");
-    this.channel = aChannel;
+    this.channel = channel;
     let self = this;
 
     info("unregistering");
@@ -79,13 +81,13 @@ ProcessChooser.prototype = {
     });
 
     info("calling switchprocessto");
-    aChannel.switchProcessTo(tabPromise, identifier);
+    aRequestor.switchProcessTo(tabPromise, identifier);
   },
 
   observe(aSubject, aTopic, aData) {
     switch (aTopic) {
       case "http-on-may-change-process":
-        this.examine(aSubject.QueryInterface(Ci.nsIHttpChannel));
+        this.examine(aSubject.QueryInterface(Ci.nsIProcessSwitchRequestor));
         break;
       default:
         ok(false, "Unexpected topic observed!");