DXR is a code search and navigation tool aimed at making sense of large projects. It supports full-text and regex searches as well as structural queries.

Header

Mercurial (cdf352f02ac4)

VCS Links

Line Code
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552
/* -*- 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/dom/CanonicalBrowsingContext.h"

#include "mozilla/dom/BrowserParent.h"
#include "mozilla/dom/BrowsingContextGroup.h"
#include "mozilla/dom/WindowGlobalParent.h"
#include "mozilla/dom/ContentProcessManager.h"
#include "mozilla/dom/MediaController.h"
#include "mozilla/dom/MediaControlService.h"
#include "mozilla/dom/PlaybackController.h"
#include "mozilla/ipc/ProtocolUtils.h"
#include "mozilla/NullPrincipal.h"

#include "nsGlobalWindowOuter.h"

using namespace mozilla::ipc;

extern mozilla::LazyLogModule gAutoplayPermissionLog;

#define AUTOPLAY_LOG(msg, ...) \
  MOZ_LOG(gAutoplayPermissionLog, LogLevel::Debug, (msg, ##__VA_ARGS__))

namespace mozilla {
namespace dom {

extern mozilla::LazyLogModule gUserInteractionPRLog;

#define USER_ACTIVATION_LOG(msg, ...) \
  MOZ_LOG(gUserInteractionPRLog, LogLevel::Debug, (msg, ##__VA_ARGS__))

CanonicalBrowsingContext::CanonicalBrowsingContext(BrowsingContext* aParent,
                                                   BrowsingContextGroup* aGroup,
                                                   uint64_t aBrowsingContextId,
                                                   uint64_t aOwnerProcessId,
                                                   uint64_t aEmbedderProcessId,
                                                   BrowsingContext::Type aType,
                                                   FieldTuple&& aFields)
    : BrowsingContext(aParent, aGroup, aBrowsingContextId, aType,
                      std::move(aFields)),
      mProcessId(aOwnerProcessId),
      mEmbedderProcessId(aEmbedderProcessId) {
  // You are only ever allowed to create CanonicalBrowsingContexts in the
  // parent process.
  MOZ_RELEASE_ASSERT(XRE_IsParentProcess());
}

/* static */
already_AddRefed<CanonicalBrowsingContext> CanonicalBrowsingContext::Get(
    uint64_t aId) {
  MOZ_RELEASE_ASSERT(XRE_IsParentProcess());
  return BrowsingContext::Get(aId).downcast<CanonicalBrowsingContext>();
}

/* static */
CanonicalBrowsingContext* CanonicalBrowsingContext::Cast(
    BrowsingContext* aContext) {
  MOZ_RELEASE_ASSERT(XRE_IsParentProcess());
  return static_cast<CanonicalBrowsingContext*>(aContext);
}

/* static */
const CanonicalBrowsingContext* CanonicalBrowsingContext::Cast(
    const BrowsingContext* aContext) {
  MOZ_RELEASE_ASSERT(XRE_IsParentProcess());
  return static_cast<const CanonicalBrowsingContext*>(aContext);
}

ContentParent* CanonicalBrowsingContext::GetContentParent() const {
  if (mProcessId == 0) {
    return nullptr;
  }

  ContentProcessManager* cpm = ContentProcessManager::GetSingleton();
  return cpm->GetContentProcessById(ContentParentId(mProcessId));
}

void CanonicalBrowsingContext::GetCurrentRemoteType(nsAString& aRemoteType,
                                                    ErrorResult& aRv) const {
  // If we're in the parent process, dump out the void string.
  if (mProcessId == 0) {
    aRemoteType.Assign(VoidString());
    return;
  }

  ContentParent* cp = GetContentParent();
  if (!cp) {
    aRv.Throw(NS_ERROR_UNEXPECTED);
    return;
  }

  aRemoteType.Assign(cp->GetRemoteType());
}

void CanonicalBrowsingContext::SetOwnerProcessId(uint64_t aProcessId) {
  MOZ_LOG(GetLog(), LogLevel::Debug,
          ("SetOwnerProcessId for 0x%08" PRIx64 " (0x%08" PRIx64
           " -> 0x%08" PRIx64 ")",
           Id(), mProcessId, aProcessId));

  mProcessId = aProcessId;
}

void CanonicalBrowsingContext::SetInFlightProcessId(uint64_t aProcessId) {
  // We can't handle more than one in-flight process change at a time.
  MOZ_ASSERT_IF(aProcessId, mInFlightProcessId == 0);

  mInFlightProcessId = aProcessId;
}

void CanonicalBrowsingContext::GetWindowGlobals(
    nsTArray<RefPtr<WindowGlobalParent>>& aWindows) {
  aWindows.SetCapacity(GetWindowContexts().Length());
  for (auto& window : GetWindowContexts()) {
    aWindows.AppendElement(static_cast<WindowGlobalParent*>(window.get()));
  }
}

WindowGlobalParent* CanonicalBrowsingContext::GetCurrentWindowGlobal() const {
  return static_cast<WindowGlobalParent*>(GetCurrentWindowContext());
}

already_AddRefed<nsIWidget>
CanonicalBrowsingContext::GetParentProcessWidgetContaining() {
  // If our document is loaded in-process, such as chrome documents, get the
  // widget directly from our outer window. Otherwise, try to get the widget
  // from the toplevel content's browser's element.
  nsCOMPtr<nsIWidget> widget;
  if (nsGlobalWindowOuter* window = nsGlobalWindowOuter::Cast(GetDOMWindow())) {
    widget = window->GetNearestWidget();
  } else if (Element* topEmbedder = Top()->GetEmbedderElement()) {
    widget = nsContentUtils::WidgetForContent(topEmbedder);
    if (!widget) {
      widget = nsContentUtils::WidgetForDocument(topEmbedder->OwnerDoc());
    }
  }

  if (widget) {
    widget = widget->GetTopLevelWidget();
  }

  return widget.forget();
}

already_AddRefed<WindowGlobalParent>
CanonicalBrowsingContext::GetEmbedderWindowGlobal() const {
  uint64_t windowId = GetEmbedderInnerWindowId();
  if (windowId == 0) {
    return nullptr;
  }

  return WindowGlobalParent::GetByInnerWindowId(windowId);
}

nsISHistory* CanonicalBrowsingContext::GetSessionHistory() {
  if (mSessionHistory) {
    return mSessionHistory;
  }

  nsCOMPtr<nsIWebNavigation> webNav = do_QueryInterface(GetDocShell());
  if (webNav) {
    RefPtr<ChildSHistory> shistory = webNav->GetSessionHistory();
    if (shistory) {
      return shistory->LegacySHistory();
    }
  }

  return nullptr;
}

JSObject* CanonicalBrowsingContext::WrapObject(
    JSContext* aCx, JS::Handle<JSObject*> aGivenProto) {
  return CanonicalBrowsingContext_Binding::Wrap(aCx, this, aGivenProto);
}

void CanonicalBrowsingContext::CanonicalDiscard() {
  if (mTabMediaController) {
    mTabMediaController->Shutdown();
    mTabMediaController = nullptr;
  }
}

void CanonicalBrowsingContext::NotifyStartDelayedAutoplayMedia() {
  if (!GetCurrentWindowGlobal()) {
    return;
  }

  // As this function would only be called when user click the play icon on the
  // tab bar. That's clear user intent to play, so gesture activate the browsing
  // context so that the block-autoplay logic allows the media to autoplay.
  NotifyUserGestureActivation();
  AUTOPLAY_LOG("NotifyStartDelayedAutoplayMedia for chrome bc 0x%08" PRIx64,
               Id());
  StartDelayedAutoplayMediaComponents();
  // Notfiy all content browsing contexts which are related with the canonical
  // browsing content tree to start delayed autoplay media.

  Group()->EachParent([&](ContentParent* aParent) {
    Unused << aParent->SendStartDelayedAutoplayMediaComponents(this);
  });
}

void CanonicalBrowsingContext::NotifyMediaMutedChanged(bool aMuted) {
  MOZ_ASSERT(!GetParent(),
             "Notify media mute change on non top-level context!");
  SetMuted(aMuted);
}

uint32_t CanonicalBrowsingContext::CountSiteOrigins(
    GlobalObject& aGlobal,
    const Sequence<OwningNonNull<BrowsingContext>>& aRoots) {
  nsTHashtable<nsCStringHashKey> uniqueSiteOrigins;

  for (const auto& root : aRoots) {
    root->PreOrderWalk([&](BrowsingContext* aContext) {
      WindowGlobalParent* windowGlobalParent =
          aContext->Canonical()->GetCurrentWindowGlobal();
      if (windowGlobalParent) {
        nsIPrincipal* documentPrincipal =
            windowGlobalParent->DocumentPrincipal();

        bool isContentPrincipal = documentPrincipal->GetIsContentPrincipal();
        if (isContentPrincipal) {
          nsCString siteOrigin;
          documentPrincipal->GetSiteOrigin(siteOrigin);
          uniqueSiteOrigins.PutEntry(siteOrigin);
        }
      }
    });
  }

  return uniqueSiteOrigins.Count();
}

void CanonicalBrowsingContext::UpdateMediaControlKeysEvent(
    MediaControlKeysEvent aEvent) {
  MediaActionHandler::HandleMediaControlKeysEvent(this, aEvent);
  Group()->EachParent([&](ContentParent* aParent) {
    Unused << aParent->SendUpdateMediaControlKeysEvent(this, aEvent);
  });
}

void CanonicalBrowsingContext::LoadURI(const nsAString& aURI,
                                       const LoadURIOptions& aOptions,
                                       ErrorResult& aError) {
  nsCOMPtr<nsIURIFixup> uriFixup = components::URIFixup::Service();

  nsCOMPtr<nsISupports> consumer = GetDocShell();
  if (!consumer) {
    consumer = GetEmbedderElement();
  }
  if (!consumer) {
    aError.Throw(NS_ERROR_UNEXPECTED);
    return;
  }

  RefPtr<nsDocShellLoadState> loadState;
  nsresult rv = nsDocShellLoadState::CreateFromLoadURIOptions(
      consumer, uriFixup, aURI, aOptions, getter_AddRefs(loadState));

  if (rv == NS_ERROR_MALFORMED_URI) {
    DisplayLoadError(aURI);
    return;
  }

  if (NS_FAILED(rv)) {
    aError.Throw(rv);
    return;
  }

  // NOTE: It's safe to call `LoadURI` without an accessor from the parent
  // process. The load will be performed with ambient "chrome" authority.
  LoadURI(nullptr, loadState, true);
}

void CanonicalBrowsingContext::PendingRemotenessChange::Complete(
    ContentParent* aContentParent) {
  if (!mPromise) {
    return;
  }

  RefPtr<CanonicalBrowsingContext> target(mTarget);
  if (target->IsDiscarded()) {
    Cancel(NS_ERROR_FAILURE);
    return;
  }

  RefPtr<WindowGlobalParent> embedderWindow = target->GetEmbedderWindowGlobal();
  if (NS_WARN_IF(!embedderWindow) || NS_WARN_IF(!embedderWindow->CanSend())) {
    Cancel(NS_ERROR_FAILURE);
    return;
  }

  RefPtr<BrowserParent> embedderBrowser = embedderWindow->GetBrowserParent();
  if (NS_WARN_IF(!embedderBrowser)) {
    Cancel(NS_ERROR_FAILURE);
    return;
  }

  // Pull load flags from our embedder browser.
  nsCOMPtr<nsILoadContext> loadContext = embedderBrowser->GetLoadContext();
  MOZ_DIAGNOSTIC_ASSERT(
      loadContext->UseRemoteTabs() && loadContext->UseRemoteSubframes(),
      "Not supported without fission");

  // NOTE: These are the only flags we actually care about
  uint32_t chromeFlags = nsIWebBrowserChrome::CHROME_REMOTE_WINDOW |
                         nsIWebBrowserChrome::CHROME_FISSION_WINDOW;
  if (loadContext->UsePrivateBrowsing()) {
    chromeFlags |= nsIWebBrowserChrome::CHROME_PRIVATE_WINDOW;
  }

  TabId tabId(nsContentUtils::GenerateTabId());
  RefPtr<BrowserBridgeParent> bridge = new BrowserBridgeParent();
  ManagedEndpoint<PBrowserBridgeChild> endpoint =
      embedderBrowser->OpenPBrowserBridgeEndpoint(bridge);
  if (NS_WARN_IF(!endpoint.IsValid())) {
    Cancel(NS_ERROR_UNEXPECTED);
    return;
  }

  RefPtr<WindowGlobalParent> oldWindow = target->GetCurrentWindowGlobal();
  RefPtr<BrowserParent> oldBrowser =
      oldWindow ? oldWindow->GetBrowserParent() : nullptr;
  bool wasRemote = oldWindow && oldWindow->IsProcessRoot();

  // Update which process is considered the current owner
  uint64_t inFlightProcessId = target->OwnerProcessId();
  target->SetInFlightProcessId(inFlightProcessId);
  target->SetOwnerProcessId(aContentParent->ChildID());

  auto resetInFlightId = [target, inFlightProcessId] {
    if (target->GetInFlightProcessId() == inFlightProcessId) {
      target->SetInFlightProcessId(0);
    } else {
      MOZ_DIAGNOSTIC_ASSERT(false, "Unexpected InFlightProcessId");
    }
  };

  // If we were in a remote frame, trigger unloading of the remote window. When
  // the original remote window acknowledges, we can clear the in-flight ID.
  if (wasRemote) {
    MOZ_DIAGNOSTIC_ASSERT(oldBrowser);
    MOZ_DIAGNOSTIC_ASSERT(oldBrowser != embedderBrowser);
    MOZ_DIAGNOSTIC_ASSERT(oldBrowser->GetBrowserBridgeParent());

    auto callback = [resetInFlightId](auto) { resetInFlightId(); };
    oldBrowser->SendWillChangeProcess(callback, callback);
    oldBrowser->Destroy();
  }

  // Tell the embedder process a remoteness change is in-process. When this is
  // acknowledged, reset the in-flight ID if it used to be an in-process load.
  {
    auto callback = [wasRemote, resetInFlightId](auto) {
      if (!wasRemote) {
        resetInFlightId();
      }
    };
    embedderWindow->SendMakeFrameRemote(target, std::move(endpoint), tabId,
                                        callback, callback);
  }

  // FIXME: We should get the correct principal for the to-be-created window so
  // we can avoid creating unnecessary extra windows in the new process.
  OriginAttributes attrs = embedderBrowser->OriginAttributesRef();
  RefPtr<nsIPrincipal> principal = embedderBrowser->GetContentPrincipal();
  if (principal) {
    attrs.SetFirstPartyDomain(
        true, principal->OriginAttributesRef().mFirstPartyDomain);
  }

  nsCOMPtr<nsIPrincipal> initialPrincipal =
      NullPrincipal::CreateWithInheritedAttributes(attrs,
                                                   /* isFirstParty */ false);
  WindowGlobalInit windowInit =
      WindowGlobalActor::AboutBlankInitializer(target, initialPrincipal);

  // Actually create the new BrowserParent actor and finish initialization of
  // our new BrowserBridgeParent.
  nsresult rv = bridge->InitWithProcess(aContentParent, EmptyString(),
                                        windowInit, chromeFlags, tabId);
  if (NS_WARN_IF(NS_FAILED(rv))) {
    Cancel(rv);
    return;
  }

  RefPtr<BrowserParent> newBrowser = bridge->GetBrowserParent();
  newBrowser->ResumeLoad(mPendingSwitchId);

  // We did it! The process switch is complete.
  mPromise->Resolve(newBrowser, __func__);
  Clear();
}

void CanonicalBrowsingContext::PendingRemotenessChange::Cancel(nsresult aRv) {
  if (!mPromise) {
    return;
  }

  mPromise->Reject(aRv, __func__);
  Clear();
}

void CanonicalBrowsingContext::PendingRemotenessChange::Clear() {
  // Make sure we don't die while we're doing cleanup.
  RefPtr<PendingRemotenessChange> kungFuDeathGrip(this);
  if (mTarget) {
    MOZ_DIAGNOSTIC_ASSERT(mTarget->mPendingRemotenessChange == this);
    mTarget->mPendingRemotenessChange = nullptr;
  }

  mPromise = nullptr;
  mTarget = nullptr;
}

CanonicalBrowsingContext::PendingRemotenessChange::~PendingRemotenessChange() {
  MOZ_ASSERT(!mPromise && !mTarget,
             "should've already been Cancel() or Complete()-ed");
}

RefPtr<CanonicalBrowsingContext::RemotenessPromise>
CanonicalBrowsingContext::ChangeFrameRemoteness(const nsAString& aRemoteType,
                                                uint64_t aPendingSwitchId) {
  // Ensure our embedder hasn't been destroyed already.
  RefPtr<WindowGlobalParent> embedderWindowGlobal = GetEmbedderWindowGlobal();
  if (!embedderWindowGlobal) {
    NS_WARNING("Non-embedded BrowsingContext");
    return RemotenessPromise::CreateAndReject(NS_ERROR_UNEXPECTED, __func__);
  }

  if (!embedderWindowGlobal->CanSend()) {
    NS_WARNING("Embedder already been destroyed.");
    return RemotenessPromise::CreateAndReject(NS_ERROR_NOT_AVAILABLE, __func__);
  }

  RefPtr<ContentParent> oldContent = GetContentParent();
  if (!oldContent || aRemoteType.IsEmpty()) {
    NS_WARNING("Cannot switch to or from non-remote frame");
    return RemotenessPromise::CreateAndReject(NS_ERROR_NOT_IMPLEMENTED,
                                              __func__);
  }

  if (aRemoteType.Equals(oldContent->GetRemoteType())) {
    NS_WARNING("Already in the correct process");
    return RemotenessPromise::CreateAndReject(NS_ERROR_FAILURE, __func__);
  }

  // Cancel ongoing remoteness changes.
  if (mPendingRemotenessChange) {
    mPendingRemotenessChange->Cancel(NS_ERROR_ABORT);
    MOZ_ASSERT(!mPendingRemotenessChange, "Should have cleared");
  }

  RefPtr<BrowserParent> embedderBrowser =
      embedderWindowGlobal->GetBrowserParent();
  MOZ_ASSERT(embedderBrowser);

  // Switching to local. No new process, so perform switch sync.
  if (aRemoteType.Equals(embedderBrowser->Manager()->GetRemoteType())) {
    if (GetCurrentWindowGlobal()) {
      MOZ_DIAGNOSTIC_ASSERT(GetCurrentWindowGlobal()->IsProcessRoot());
      RefPtr<BrowserParent> oldBrowser =
          GetCurrentWindowGlobal()->GetBrowserParent();

      RefPtr<CanonicalBrowsingContext> target(this);
      SetInFlightProcessId(OwnerProcessId());
      oldBrowser->SendWillChangeProcess(
          [target](bool aSuccess) { target->SetInFlightProcessId(0); },
          [target](mozilla::ipc::ResponseRejectReason aReason) {
            target->SetInFlightProcessId(0);
          });
      oldBrowser->Destroy();
    }

    SetOwnerProcessId(embedderBrowser->Manager()->ChildID());
    Unused << embedderWindowGlobal->SendMakeFrameLocal(this, aPendingSwitchId);
    return RemotenessPromise::CreateAndResolve(embedderBrowser, __func__);
  }

  // Switching to remote. Wait for new process to launch before switch.
  auto promise = MakeRefPtr<RemotenessPromise::Private>(__func__);
  RefPtr<PendingRemotenessChange> change =
      new PendingRemotenessChange(this, promise, aPendingSwitchId);
  mPendingRemotenessChange = change;

  ContentParent::GetNewOrUsedBrowserProcessAsync(
      /* aFrameElement = */ nullptr,
      /* aRemoteType = */ aRemoteType,
      /* aPriority = */ hal::PROCESS_PRIORITY_FOREGROUND,
      /* aOpener = */ nullptr,
      /* aPreferUsed = */ false)
      ->Then(
          GetMainThreadSerialEventTarget(), __func__,
          [change](ContentParent* aContentParent) {
            change->Complete(aContentParent);
          },
          [change](LaunchError aError) { change->Cancel(NS_ERROR_FAILURE); });
  return promise.forget();
}

already_AddRefed<Promise> CanonicalBrowsingContext::ChangeFrameRemoteness(
    const nsAString& aRemoteType, uint64_t aPendingSwitchId, ErrorResult& aRv) {
  nsIGlobalObject* global = xpc::NativeGlobal(xpc::PrivilegedJunkScope());

  RefPtr<Promise> promise = Promise::Create(global, aRv);
  if (aRv.Failed()) {
    return nullptr;
  }

  ChangeFrameRemoteness(aRemoteType, aPendingSwitchId)
      ->Then(
          GetMainThreadSerialEventTarget(), __func__,
          [promise](BrowserParent* aBrowserParent) {
            promise->MaybeResolve(aBrowserParent->Manager()->ChildID());
          },
          [promise](nsresult aRv) { promise->MaybeReject(aRv); });
  return promise.forget();
}

MediaController* CanonicalBrowsingContext::GetMediaController() {
  // We would only create one media controller per tab, so accessing the
  // controller via the top-level browsing context.
  if (GetParent()) {
    return Cast(Top())->GetMediaController();
  }

  MOZ_ASSERT(!GetParent(),
             "Must access the controller from the top-level browsing context!");
  // Only content browsing context can create media controller, we won't create
  // controller for chrome document, such as the browser UI.
  if (!mTabMediaController && !IsDiscarded() && IsContent()) {
    mTabMediaController = new MediaController(Id());
  }
  return mTabMediaController;
}

NS_IMPL_CYCLE_COLLECTION_INHERITED(CanonicalBrowsingContext, BrowsingContext,
                                   mSessionHistory)

NS_IMPL_ADDREF_INHERITED(CanonicalBrowsingContext, BrowsingContext)
NS_IMPL_RELEASE_INHERITED(CanonicalBrowsingContext, BrowsingContext)

NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(CanonicalBrowsingContext)
NS_INTERFACE_MAP_END_INHERITING(BrowsingContext)

}  // namespace dom
}  // namespace mozilla