import changes from `dev' branch of rmottola/Arctic-Fox:

- Bug 1261720 (part 1) - Separate js::ClassExtension from js::Class. r=jorendorff,bz. (6368952442)
- Bug 1261720 (part 2) - Move ClassExtension::isWrappedNative into js::Class::flags. r=jorendorff. (554fe695c2)
- Bug 1261723 (part 1) - Rename js::Class::ops as oOps. r=efaust. (e9dace574c)
- Bug 1261723 (part 2) - Separate class ops from js::Class. code=njn,h4writer. r=efaust,bz. (54bc06aec6)
- Bug 1263865 - Check the return value of GetSelfHostedFunction in ArraySpeciesCreate. r=efaust (cc6e1c0e50)
- Bug 1248948 - Don't pass non-SavedFrame objects to SavedFrame JSAPI functions; r=tromey r=evilpie (8c753c3c89)
- Bug 1260475 - Add an option to disable GC slices triggered by painting. r=terrence a=kwierso (df86be5e34)
- Bug 1263803 - Change AllocateArrayBuffer to receive byteLength instead of nelements. r=lth (751e333ff0)
- Bug 1264941 - Use byteLength of source typedArray in CloneArrayBuffer. r=lth (0095fce3aa)
- Bug 1263879 - Check the return value of AtomizeString in str_replace_string_raw. r=h4writer (31e1470bc3)
- Bug 1258453 - Compact arenas containing strings r=terrence (f6b4029d79)
- Bug 1258095 - patch 1/3 - OSFileSystem should have the root == the directory root, r=smaug (8cf74899f4)
- Bug 1258095 - patch 2/3 - Implement Directory::GetPath() correctly, r=smaug (776f503c98)
- Bug 1258095 - patch 3/3 - Directory tasks should use FallibleArray, r=smaug (b4888c92b9)
- Bug 1258221 - patch 1 - File::CreateFromFile only for main-thread, r=smaug (c106b37cb4)
- Bug 1258056 - Propagate the window opener full page zoom across the IPC layer; r=smaug (511386589f)
- Bug 1248772 - Trigger a OS window focus in ServiceWorkerClients::OpenWindow. r=ehsan (feb322b9f0)
- Bug 1259707 - Fix confusion between desktop and CSS pixels when session-restore is constraining window to the available screen space. r=emk (def9cc918b)
- Bug 1250266 - Always send a TTL in the Push mochitests. r=benbangert (43c7bde7b8)
- Bug 1244816 - Create PushService mock for mochitests backed by a mock web socket. r=kitcambridge (92270cbae5)
- Bug 1257395: Update comments for GCHashTable and GCPolicy. DONTBUILD r=terrence (fee0311ea0)
- Bug 1263772 - Use WeakCache wrapper to sweep BaseShape table; r=jonco (a0e015667c)
- Bug 1263777 - Use WeakCache to sweep the InitialShapeTable; r=jonco (84d1591585)
- Bug 1132502 (part 1) - Abort if compartmentStats is null during memory reporting. r=jandem. (bd144192b1)
- Bug 1132502 (part 2) - Don't call AddClassInfo() for BaseShapes. r=jandem. (10881fe48c)
- Bug 1259490 - Update the DtoA cache after compacting GC; r=jandem (6e3139501c)
- Bug 1257903 - Fix spurious GC hazard on a CLOSED TREE r=me (ce2935d8b2)
- Bug 1259042 - Re-introduce a version of ZoneCellIter for use under GC r=terrence (d1e4ca6e30)
- Bug 1259180 - Compact arenas containing scripts r=terrence (365d22ab00)
- Bug 1258407 - Limit GC heap growth parameters r=sfink (1c9ffb0e3f)
- Bug 1263966 - Compact arenas containing lazy scripts r=terrence (e22c571c37)
- Bug 1266107 - Update type descriptors first when compacting r=terrence (4c2ca98bb3)
- Bug 1266105 - Only purge runtime tables once per slice when compacting r=terrence (74e2977241)
- Bug 1263769 - Sweep WeakCaches in parallel; r=sfink (54b077b37b)
- Bug 1266107 - Track all existing typed object descriptor objects r=terrence (bc60425bf6)
- Bug 1260198 - Clear per-zone string cache after compacting r=terrence (c3002b8021)
- Bug 1259306 - Trace ShapeTables r=terrence (15abb48a33)
- Bug 1262203 - Skip shape table tracing where possible r=terrence (8a1ec15053)
- Bug 1164432 - Update test_try_registering_offline_disabled.html to use mock push server. r=kitcambridge (6d52de1a17)
- Bug 1263857 - Initialize the slots of the match result object before creating properties in generateRegExpMatcherStub. r=h4writer (802af47b3a)
- Bug 1263549 - Fix inlined RegExpPrototypeOptimizable and RegExpInstanceOptimizable. r=h4writer (5565bca590)
- Bug 1264998 - CodeGeneratorShared::assignBailoutId: Properly handle allocation errors. r=h4writer (258cbfc0b6)
- Bug 1257408 - Fix VS2015 C4312 warnings in js/src. r=nbp (d52a4d1fe7)
- Bug 1220466 - Don't build event region display items for pseudo stacking contexts, unless they are also an AGR. r=mstange (9f9a2c7eba)
- Bug 1220466 - Avoid doing unnecessary layer building work for inactive layers. r=mstange (372097e6df)
- Bug 1239151. Increase skia font cache size to 10mb on non-android platforms. r=lsalzman (8a2029da40)
- Bug 1255068 - Do not allow empty transaction transform changes if the scroll position has changed since the last paint. r=kats, r=mattwoodrow (f4a42e10c8)
- Bug 1255068 - Add a check for null scrollid. r=kats (3ddbb78fd3)
- Bug 1258910 - IonMonkey: MIPS: Implement float-point conditional move instructions. r=huangwenjun06 (b53499103b)
- Bug 1258910 - OdinMonkey: MIPS64: Implement AsmSelectI64. r=bbouvier (a36cfffa1d)
- Bug 1258910 - OdinMonkey: MIPS: Implement AsmSelect. r=bbouvier (e458724bc1)
- Bug 1254500 - IonMonkey: MIPS: Implement ma_ctz. r=arai (c8bfd7a6c9)
- Bug 1254500 - IonMonkey: MIPS: Implement CodeGeneratorMIPSShared::visitCtzI. r=arai (b65dad7d1b)
- Bug 1254500 - IonMonkey: MIPS: Implement CodeGeneratorMIPSShared::visitPopcntI. r=arai (58c00b603e)
- Bug 1258105 - Port object length stubs to CacheIR. r=efaust (ed0ec07678)
- Bug 1258301 - Use TraceNullableEdge for CacheIR pointers. r=jonco (3342ef24b4)
- Bug 1258327 - Part 1: Move ToAddress from CodeGeneratorMIPSShared to CodeGeneratorShared. r=hev (59e7494f02)
- Bug 1258327 - Part 2: Remove Operand variant from bailoutCmp32. r=nbp (c4609af383)
- Bug 1258327 - Part 3: Remove Operand variant from branch32 except x86-shared. r=nbp (dca4bc7577)
- Bug 1258327 - Part 4: Remove ToOperand call from arm CodeGenerator. r=jandem (395d7a004f)
- Bug 1258327 - Part 5: Remove dummy ToOperand definition from arm64 CodeGenerator. r=jandem (bc447cb6aa)
- Bug 1258327 - Part 6: Remove ToOperand call from mips-shared and mips64 CodeGenerator. r=hev (d01b028148)
- Bug 1258327 - Part 7: Move ToOperand from CodeGeneratorShared to CodeGeneratorX86Shared. r=nbp (71449d7c62)
- Bug 1248412 - Prevent immediate bailout from innermost for-of loops. r=h4writer (616897a580)
- Bug 1261326 - Fix a bogus assert. r=bhackett (ff715a7954)
- Bug 1260371 - Rearrange RelocationOverlay so that magic field does not overlay inline string chars r=terrence (f88fbb8927)
- Bug 1262203 - Do GC relocation writes in order; r=sfink (b82a25dd15)
- Bug 1247909 - Move MFunctionEnvironment after the entry resume points operands. r=h4writer (29d8d1c2df)
- Bug 1259925 - Port ModuleNamespace getprop stub to CacheIR. r=efaust (b31980bdc3)
- Bug 1264561 - Fix ClassOps::call and ClassOps::construct address calculation in visitIsCallable and visitIsConstructor. r=efaust (172037857b)
- Bug 1264823 - Add pre-barrier to the elements of mapIterationResultPair. r=jandem (b2e451c371)
- Bug 1263609: SharedStubs - Allow JSOP_POW in ion codegen ON CLOSED TREE, r=bbouvier (16bb4ca9af)
- Bug 1265159 - IonMonkey: Throw error when popping from an empty array in MArrayPopShift, r=jandem (e3a1b08614)
- Bug 1259392 - nail down isLockFree(4) for good. r=jolesen (72fa558eec)
- Bug 1244252 - Don't check object group generation when generating code to create unboxed objects off thread, r=terrence. (4191175759)
- Bug 1254578 - Fix OOM case when rematerializing frames. (r=jandem) (a213756a2b)
- Bug 1263139 - Apply ToString to non-standard flags argument of String.prototype.{match,search,replace}. r=till (91c8f6f592)
- Bug 1257810 - ReleaseAcquire should be adequate for a counter; r=sfink (e394a21b3d)
- Bug 1251833 - Part 4: Remove some unneeded qualification from GCRuntime and friends. r=terrence (e77de1a3ac)
- Bug 1260371 - Forward another pointer during TypedObject tracing to fix bustage r=me (24636e9463)
- Bug 1266107 - Simplify typed object tracing now type descriptors are traced first r=terrence (6872be4bfa)
- Bug 1260998 - Add support for HOST_CPPFLAGS for consistency. r=nalexander (9fe0ddee7e)
- Bug 1105556 - Don't call CheckLoadURIWithPrincipal() in DoCheckLoadURIChecks() for TYPE_DOCUMENT loads where we don't have a loadingPrincipal. Ensure SEC_COOKIES_SAME_ORIGIN isn't set for TYPE_DOCUMENT loads in CheckChannel(). r=ckerschb, sicking (fbebbf1017)
- Bug 1195172 - Use channel->ascynOpen2 layout/style/FontFaceSet.cpp (r=bz,cam) (3e943da95c)
- Bug 1250986 - Make Request.referrer a USVString; r=bzbarsky (6987ab9838)
- Bug 1250987 - Make RequestInit.body nullable; r=bzbarsky (2496ebea1f)
- Bug 1251448 - Add support for RequestInit.referrer; r=jdm (dcf1a668f8)
- Bug 1250985 - Part 1: Add a way to identify whether a WebIDL dictionary has any members present; r=bzbarsky (7ddd6e8043)
- Bug 1250985 - Part 2: Prevent copy constructing a Request object with navigate mode if a RequestInit member is present; r=bzbarsky (24c8c1ca56)
- Bug 1184550 - Move the check for bodyUsed before the check for a null body so subsequent fetches with the same Request fail. r=bkelly (60837c04eb)
- Bug 1251872 - Part 1: Implement Request.referrerPolicy; r=jdm (bd024c0614)
- bug 1252687 - make Migration's ctor constexpr r=bz (793d608bcd)
- Bug 1251872 - Part 2: Store the Request referrerPolicy in the DOM Cache; r=bkelly (e1511c07a6)
- Bug 1251229 P2 Add wpt test verifying FetchEvent.request.url does not include fragments. r=ehsan (1d74e2491e)
- Bug 1251229 P1 Strip fragment from request URL when creating FetchEvent. r=ehsan (5faddecc78)
- Bug 1120715 - Part 4: Add tests for Request.cache; r=bkelly (81537bd125)
- Bug 1237455 P1 Make file_CrossSiteXHR_server.sjs check headers on redirects. r=ehsan (597fdf223d)
- Bug 1237455 P2 Test headers on redirects in fetch mochitests. r=ehsan (2a19ac6a44)
- Bug 1237455 P3 Add a version of test_fetch_cors that reroutes through an empty service worker. r=ehsan (0550d5e115)
- Bug 1205288 - implement and test fetch spec changes for blob scheme with non-GET method. r=bkelly (bb519b1c71)
- Bug 1237455 P4 Create helper method to set fetch request headers. r=ehsan (20266aa708)
- Bug 1237455 P5 Set headers on fetch() redirects. r=ehsan (95dcfe7f71)
- Bug 1120715 - Part 5: Treat a default cache mode Request with a revalidation header as no-store; r=bkelly (4182fded21)
- fix! (c3097a682a)
- Bug 1204520 - Remove unused return value from FetchDriver::FailWithNetworkError. r=jdm (ddd84df514)
- Bug 1253054 - Stop warning if request has already failed. r=bkelly (52eb17afd2)
- Bug 1176824 - Intermittent browser_test_web_manifest.js. r=ckerschb (b8c1fc5757)
- Bug 1242051 - Add inter-directory test support file dependencies to ini manifests. r=gps (5d06d6b00c)
- Bug 1250048 - CSP manifest-src doesn't override default-src. r=ckerschb,bkelly,ehsan (3d77b91226)
- Bug 1262624 Move service worker wpt tests out of mozilla dir so they will be upstreamed. r=jgraham (cf1f010cd2)
- Bug 1263469 P1 Set FetchEvent.request.cache value correctly for non-fetch channels. r=mayhemer (0fac232769)
- Bug 1263469 P2 Validate FetchEvent.request.cache in refresh mochitest. r=ehsan (de0db7da84)
- Bug 1263469 P3 Test FetchEvent.request.cache value on reload in wpt test. r=ehsan (8b4fc58d08)
- Bug 1263469 P4 Update test_eventsource_intercept.html to validate FetchEvent.request.cache. r=ehsan (81843666c0)
- Bug 1263469 P5 Add a wpt test case for EventSource. r=ehsan (a32cbbaf80)
- Bug 1265941 - Rename the ReferrerPolicy "origin-only" enum value to "origin"; r=jdm (1b1dfcebbc)

dom/fetch/FetchDriver.cpp

@@ -42,7 +42,7 @@ namespace mozilla {
 namespace dom {
 
 NS_IMPL_ISUPPORTS(FetchDriver,
-                  nsIStreamListener, nsIInterfaceRequestor,
+                  nsIStreamListener, nsIChannelEventSink, nsIInterfaceRequestor,
                   nsIThreadRetargetableStreamListener)
 
 FetchDriver::FetchDriver(InternalRequest* aRequest, nsIPrincipal* aPrincipal,
@@ -129,6 +129,15 @@ FetchDriver::HttpFetch()
     return NS_ERROR_DOM_BAD_URI;
   }
 
+  // non-GET requests aren't allowed for blob.
+  if (IsBlobURI(uri)) {
+    nsAutoCString method;
+    mRequest->GetMethod(method);
+    if (!method.EqualsLiteral("GET")) {
+      return NS_ERROR_DOM_NETWORK_ERR;
+    }
+  }
+
   // Step 2 deals with letting ServiceWorkers intercept requests. This is
   // handled by Necko after the channel is opened.
   // FIXME(nsm): Bug 1119026: The channel's skip service worker flag should be
@@ -221,11 +230,16 @@ FetchDriver::HttpFetch()
 
   mLoadGroup = nullptr;
 
-  // FIXME(nsm): Bug 1120715.
-  // Step 3.4 "If request's cache mode is default and request's header list
-  // contains a header named `If-Modified-Since`, `If-None-Match`,
-  // `If-Unmodified-Since`, `If-Match`, or `If-Range`, set request's cache mode
-  // to no-store."
+  // Insert ourselves into the notification callbacks chain so we can set
+  // headers on redirects.
+#ifdef DEBUG
+  {
+    nsCOMPtr<nsIInterfaceRequestor> notificationCallbacks;
+    chan->GetNotificationCallbacks(getter_AddRefs(notificationCallbacks));
+    MOZ_ASSERT(!notificationCallbacks);
+  }
+#endif
+  chan->SetNotificationCallbacks(this);
 
   // Step 3.5 begins "HTTP network or cache fetch".
   // HTTP network or cache fetch
@@ -240,33 +254,41 @@ FetchDriver::HttpFetch()
     NS_ENSURE_SUCCESS(rv, rv);
 
     // Set the same headers.
-    AutoTArray<InternalHeaders::Entry, 5> headers;
-    mRequest->Headers()->GetEntries(headers);
-    bool hasAccept = false;
-    for (uint32_t i = 0; i < headers.Length(); ++i) {
-      if (!hasAccept && headers[i].mName.EqualsLiteral("accept")) {
-        hasAccept = true;
-      }
-      if (headers[i].mValue.IsEmpty()) {
-        httpChan->SetEmptyRequestHeader(headers[i].mName);
-      } else {
-        httpChan->SetRequestHeader(headers[i].mName, headers[i].mValue, false /* merge */);
-      }
-    }
-
-    if (!hasAccept) {
-      httpChan->SetRequestHeader(NS_LITERAL_CSTRING("accept"),
-                                 NS_LITERAL_CSTRING("*/*"),
-                                 false /* merge */);
-    }
+    SetRequestHeaders(httpChan);
 
     // Step 2. Set the referrer.
     nsAutoString referrer;
     mRequest->GetReferrer(referrer);
+    ReferrerPolicy referrerPolicy = mRequest->ReferrerPolicy_();
+    net::ReferrerPolicy net_referrerPolicy = net::RP_Unset;
+    switch (referrerPolicy) {
+    case ReferrerPolicy::_empty:
+      net_referrerPolicy = net::RP_Default;
+      break;
+    case ReferrerPolicy::No_referrer:
+      net_referrerPolicy = net::RP_No_Referrer;
+      break;
+    case ReferrerPolicy::No_referrer_when_downgrade:
+      net_referrerPolicy = net::RP_No_Referrer_When_Downgrade;
+      break;
+    case ReferrerPolicy::Origin:
+      net_referrerPolicy = net::RP_Origin;
+      break;
+    case ReferrerPolicy::Origin_when_cross_origin:
+      net_referrerPolicy = net::RP_Origin_When_Crossorigin;
+      break;
+    case ReferrerPolicy::Unsafe_url:
+      net_referrerPolicy = net::RP_Unsafe_URL;
+      break;
+    default:
+      MOZ_ASSERT_UNREACHABLE("Invalid ReferrerPolicy enum value?");
+      break;
+    }
     if (referrer.EqualsLiteral(kFETCH_CLIENT_REFERRER_STR)) {
       rv = nsContentUtils::SetFetchReferrerURIWithPolicy(mPrincipal,
                                                          mDocument,
-                                                         httpChan);
+                                                         httpChan,
+                                                         net_referrerPolicy);
       NS_ENSURE_SUCCESS(rv, rv);
     } else if (referrer.IsEmpty()) {
       rv = httpChan->SetReferrerWithPolicy(nullptr, net::RP_No_Referrer);
@@ -275,32 +297,20 @@ FetchDriver::HttpFetch()
       // From "Determine request's Referrer" step 3
       // "If request's referrer is a URL, let referrerSource be request's
       // referrer."
-      //
-      // XXXnsm - We never actually hit this from a fetch() call since both
-      // fetch and Request() create a new internal request whose referrer is
-      // always set to about:client. Should we just crash here instead until
-      // someone tries to use FetchDriver for non-fetch() APIs?
       nsCOMPtr<nsIURI> referrerURI;
       rv = NS_NewURI(getter_AddRefs(referrerURI), referrer, nullptr, nullptr);
       NS_ENSURE_SUCCESS(rv, rv);
 
+      uint32_t documentReferrerPolicy = mDocument ? mDocument->GetReferrerPolicy() :
+                                                    net::RP_Default;
       rv =
         httpChan->SetReferrerWithPolicy(referrerURI,
-                                        mDocument ? mDocument->GetReferrerPolicy() :
-                                                    net::RP_Default);
+                                        referrerPolicy == ReferrerPolicy::_empty ?
+                                          documentReferrerPolicy :
+                                          net_referrerPolicy);
       NS_ENSURE_SUCCESS(rv, rv);
     }
 
-    // Step 3 "If HTTPRequest's force Origin header flag is set..."
-    if (mRequest->ForceOriginHeader()) {
-      nsAutoString origin;
-      rv = nsContentUtils::GetUTFOrigin(mPrincipal, origin);
-      NS_ENSURE_SUCCESS(rv, rv);
-
-      httpChan->SetRequestHeader(NS_LITERAL_CSTRING("origin"),
-                                 NS_ConvertUTF16toUTF8(origin),
-                                 false /* merge */);
-    }
     // Bug 1120722 - Authorization will be handled later.
     // Auth may require prompting, we don't support it yet.
     // The next patch in this same bug prevents this from aborting the request.
@@ -312,12 +322,11 @@ FetchDriver::HttpFetch()
     // dom/workers/ServiceWorkerManager.cpp
     internalChan->SetCorsMode(static_cast<uint32_t>(mRequest->Mode()));
     internalChan->SetRedirectMode(static_cast<uint32_t>(mRequest->GetRedirectMode()));
+    mRequest->MaybeSkipCacheIfPerformingRevalidation();
     internalChan->SetFetchCacheMode(static_cast<uint32_t>(mRequest->GetCacheMode()));
   }
 
   // Step 5. Proxy authentication will be handled by Necko.
-  // FIXME(nsm): Bug 1120715.
-  // Step 7-10. "If request's cache mode is neither no-store nor reload..."
 
   // Continue setting up 'HTTPRequest'. Content-Type and body data.
   nsCOMPtr<nsIUploadChannel2> uploadChan = do_QueryInterface(chan);
@@ -401,7 +410,7 @@ FetchDriver::BeginAndGetFilteredResponse(InternalResponse* aResponse,
   return filteredResponse.forget();
 }
 
-nsresult
+void
 FetchDriver::FailWithNetworkError()
 {
   workers::AssertIsOnMainThread();
@@ -412,7 +421,6 @@ FetchDriver::FailWithNetworkError()
     mObserver->OnResponseEnd();
     mObserver = nullptr;
   }
-  return NS_OK;
 }
 
 namespace {
@@ -459,7 +467,7 @@ FetchDriver::OnStartRequest(nsIRequest* aRequest,
 
   nsresult rv;
   aRequest->GetStatus(&rv);
-  if (NS_WARN_IF(NS_FAILED(rv))) {
+  if (NS_FAILED(rv)) {
     FailWithNetworkError();
     return rv;
   }
@@ -662,6 +670,21 @@ FetchDriver::OnStopRequest(nsIRequest* aRequest,
   return NS_OK;
 }
 
+NS_IMETHODIMP
+FetchDriver::AsyncOnChannelRedirect(nsIChannel* aOldChannel,
+                                    nsIChannel* aNewChannel,
+                                    uint32_t aFlags,
+                                    nsIAsyncVerifyRedirectCallback *aCallback)
+{
+  nsCOMPtr<nsIHttpChannel> httpChannel = do_QueryInterface(aNewChannel);
+  if (httpChannel) {
+    SetRequestHeaders(httpChannel);
+  }
+
+  aCallback->OnRedirectVerifyCallback(NS_OK);
+  return NS_OK;
+}
+
 NS_IMETHODIMP
 FetchDriver::CheckListenerChain()
 {
@@ -671,6 +694,11 @@ FetchDriver::CheckListenerChain()
 NS_IMETHODIMP
 FetchDriver::GetInterface(const nsIID& aIID, void **aResult)
 {
+  if (aIID.Equals(NS_GET_IID(nsIChannelEventSink))) {
+    *aResult = static_cast<nsIChannelEventSink*>(this);
+    NS_ADDREF_THIS();
+    return NS_OK;
+  }
   if (aIID.Equals(NS_GET_IID(nsIStreamListener))) {
     *aResult = static_cast<nsIStreamListener*>(this);
     NS_ADDREF_THIS();
@@ -693,5 +721,40 @@ FetchDriver::SetDocument(nsIDocument* aDocument)
   mDocument = aDocument;
 }
 
+void
+FetchDriver::SetRequestHeaders(nsIHttpChannel* aChannel) const
+{
+  MOZ_ASSERT(aChannel);
+
+  AutoTArray<InternalHeaders::Entry, 5> headers;
+  mRequest->Headers()->GetEntries(headers);
+  bool hasAccept = false;
+  for (uint32_t i = 0; i < headers.Length(); ++i) {
+    if (!hasAccept && headers[i].mName.EqualsLiteral("accept")) {
+      hasAccept = true;
+    }
+    if (headers[i].mValue.IsEmpty()) {
+      aChannel->SetEmptyRequestHeader(headers[i].mName);
+    } else {
+      aChannel->SetRequestHeader(headers[i].mName, headers[i].mValue, false /* merge */);
+    }
+  }
+
+  if (!hasAccept) {
+    aChannel->SetRequestHeader(NS_LITERAL_CSTRING("accept"),
+                               NS_LITERAL_CSTRING("*/*"),
+                               false /* merge */);
+  }
+
+  if (mRequest->ForceOriginHeader()) {
+    nsAutoString origin;
+    if (NS_SUCCEEDED(nsContentUtils::GetUTFOrigin(mPrincipal, origin))) {
+      aChannel->SetRequestHeader(NS_LITERAL_CSTRING("origin"),
+                                 NS_ConvertUTF16toUTF8(origin),
+                                 false /* merge */);
+    }
+  }
+}
+
 } // namespace dom
 } // namespace mozilla