summaryrefslogtreecommitdiffstats
path: root/layout/style/ImageLoader.cpp
blob: af3e9230532774d1231ae81f64d0a0d039b85da4 (plain)
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
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
/* -*- 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/. */

/* A class that handles style system image loads (other image loads are handled
 * by the nodes in the content tree).
 */

#include "mozilla/css/ImageLoader.h"

#include "mozilla/dom/Document.h"
#include "mozilla/dom/DocumentInlines.h"
#include "mozilla/dom/ImageTracker.h"
#include "nsContentUtils.h"
#include "nsIReflowCallback.h"
#include "nsLayoutUtils.h"
#include "nsError.h"
#include "nsCanvasFrame.h"
#include "nsDisplayList.h"
#include "nsIFrameInlines.h"
#include "imgIContainer.h"
#include "imgINotificationObserver.h"
#include "Image.h"
#include "mozilla/PresShell.h"
#include "mozilla/ProfilerLabels.h"
#include "mozilla/StaticPtr.h"
#include "mozilla/SVGObserverUtils.h"
#include "mozilla/layers/WebRenderUserData.h"
#include "nsTHashSet.h"

using namespace mozilla::dom;

namespace mozilla::css {

// This is a singleton observer which looks in the `GlobalRequestTable` to look
// at which loaders to notify.
struct GlobalImageObserver final : public imgINotificationObserver {
  NS_DECL_ISUPPORTS
  NS_DECL_IMGINOTIFICATIONOBSERVER

  GlobalImageObserver() = default;

 private:
  virtual ~GlobalImageObserver() = default;
};

NS_IMPL_ADDREF(GlobalImageObserver)
NS_IMPL_RELEASE(GlobalImageObserver)

NS_INTERFACE_MAP_BEGIN(GlobalImageObserver)
  NS_INTERFACE_MAP_ENTRY(imgINotificationObserver)
NS_INTERFACE_MAP_END

// Data associated with every started load.
struct ImageTableEntry {
  // Set of all ImageLoaders that have registered this URL and care for updates
  // for it.
  nsTHashSet<ImageLoader*> mImageLoaders;

  // The amount of style values that are sharing this image.
  uint32_t mSharedCount = 1;
};

using GlobalRequestTable =
    nsClassHashtable<nsRefPtrHashKey<imgIRequest>, ImageTableEntry>;

// A table of all loads, keyed by their id mapping them to the set of
// ImageLoaders they have been registered in, and recording their "canonical"
// image request.
//
// We use the load id as the key since we can only access sImages on the
// main thread, but LoadData objects might be destroyed from other threads,
// and we don't want to leave dangling pointers around.
static StaticAutoPtr<GlobalRequestTable> sImages;
static StaticRefPtr<GlobalImageObserver> sImageObserver;

/* static */
void ImageLoader::Init() {
  sImages = new GlobalRequestTable();
  sImageObserver = new GlobalImageObserver();
}

/* static */
void ImageLoader::Shutdown() {
  for (const auto& entry : *sImages) {
    imgIRequest* imgRequest = entry.GetKey();
    // All the images we put in sImages are imgRequestProxy, see LoadImage, but
    // it's non-trivial to make the hash table to use that without changing a
    // lot of other code.
    auto* req = static_cast<imgRequestProxy*>(imgRequest);
    req->SetCancelable(true);
    req->CancelAndForgetObserver(NS_BINDING_ABORTED);
  }

  sImages = nullptr;
  sImageObserver = nullptr;
}

void ImageLoader::DropDocumentReference() {
  MOZ_ASSERT(NS_IsMainThread());

  // It's okay if GetPresContext returns null here (due to the presshell pointer
  // on the document being null) as that means the presshell has already
  // been destroyed, and it also calls ClearFrames when it is destroyed.
  ClearFrames(GetPresContext());

  mDocument = nullptr;
}

// Arrays of requests and frames are sorted by their pointer address,
// for faster lookup.
template <typename Elem, typename Item,
          typename Comparator = nsDefaultComparator<Elem, Item>>
static size_t GetMaybeSortedIndex(const nsTArray<Elem>& aArray,
                                  const Item& aItem, bool* aFound,
                                  Comparator aComparator = Comparator()) {
  size_t index = aArray.IndexOfFirstElementGt(aItem, aComparator);
  *aFound = index > 0 && aComparator.Equals(aItem, aArray.ElementAt(index - 1));
  return index;
}

// Returns true if an async decode is triggered for aRequest, and thus we will
// get an OnFrameComplete callback for this request eventually.
static bool TriggerAsyncDecodeAtIntrinsicSize(imgIRequest* aRequest) {
  uint32_t status = 0;
  // Don't block onload if we've already got a frame complete status
  // (since in that case the image is already loaded), or if we get an
  // error status (since then we know the image won't ever load).
  if (NS_SUCCEEDED(aRequest->GetImageStatus(&status))) {
    if (status & imgIRequest::STATUS_FRAME_COMPLETE) {
      // Already decoded, no need to do it again.
      return false;
    }
    if (status & imgIRequest::STATUS_ERROR) {
      // Already errored, this would be useless.
      return false;
    }
  }

  // We want to request decode in such a way that avoids triggering sync decode.
  // First, we attempt to convert the aRequest into a imgIContainer. If that
  // succeeds, then aRequest has an image and we can request decoding for size
  // at zero size, the size will be ignored because we don't pass the
  // FLAG_HIGH_QUALITY_SCALING flag and an async decode (because we didn't pass
  // any sync decoding flags) at the intrinsic size will be requested. If the
  // conversion to imgIContainer is unsuccessful, then that means aRequest
  // doesn't have an image yet, which means we can safely call StartDecoding()
  // on it without triggering any synchronous work.
  nsCOMPtr<imgIContainer> imgContainer;
  aRequest->GetImage(getter_AddRefs(imgContainer));
  if (imgContainer) {
    imgContainer->RequestDecodeForSize(gfx::IntSize(0, 0),
                                       imgIContainer::DECODE_FLAGS_DEFAULT);
  } else {
    // It's safe to call StartDecoding directly, since it can't
    // trigger synchronous decode without an image. Flags are ignored.
    aRequest->StartDecoding(imgIContainer::FLAG_NONE);
  }
  return true;
}

void ImageLoader::AssociateRequestToFrame(imgIRequest* aRequest,
                                          nsIFrame* aFrame, Flags aFlags) {
  MOZ_ASSERT(NS_IsMainThread());
  MOZ_ASSERT(!(aFlags & Flags::IsBlockingLoadEvent),
             "Shouldn't be used in the public API");

  {
    nsCOMPtr<imgINotificationObserver> observer;
    aRequest->GetNotificationObserver(getter_AddRefs(observer));
    if (!observer) {
      // The request has already been canceled, so ignore it. This is ok because
      // we're not going to get any more notifications from a canceled request.
      return;
    }
    MOZ_ASSERT(observer == sImageObserver);
  }

  auto* const frameSet =
      mRequestToFrameMap
          .LookupOrInsertWith(
              aRequest,
              [&] {
                mDocument->ImageTracker()->Add(aRequest);

                if (auto entry = sImages->Lookup(aRequest)) {
                  DebugOnly<bool> inserted =
                      entry.Data()->mImageLoaders.EnsureInserted(this);
                  MOZ_ASSERT(inserted);
                } else {
                  MOZ_ASSERT_UNREACHABLE(
                      "Shouldn't be associating images not in sImages");
                }

                if (nsPresContext* presContext = GetPresContext()) {
                  nsLayoutUtils::RegisterImageRequestIfAnimated(
                      presContext, aRequest, nullptr);
                }
                return MakeUnique<FrameSet>();
              })
          .get();

  auto* const requestSet =
      mFrameToRequestMap
          .LookupOrInsertWith(aFrame,
                              [=]() {
                                aFrame->SetHasImageRequest(true);
                                return MakeUnique<RequestSet>();
                              })
          .get();

  // Add frame to the frameSet, and handle any special processing the
  // frame might require.
  FrameWithFlags fwf(aFrame);
  FrameWithFlags* fwfToModify = &fwf;

  // See if the frameSet already has this frame.
  bool found;
  uint32_t i =
      GetMaybeSortedIndex(*frameSet, fwf, &found, FrameOnlyComparator());
  if (found) {
    // We're already tracking this frame, so prepare to modify the
    // existing FrameWithFlags object.
    fwfToModify = &frameSet->ElementAt(i - 1);
  }

  // Check if the frame requires special processing.
  if (aFlags & Flags::RequiresReflowOnSizeAvailable) {
    MOZ_ASSERT(!(aFlags &
                 Flags::RequiresReflowOnFirstFrameCompleteAndLoadEventBlocking),
               "These two are exclusive");
    fwfToModify->mFlags |= Flags::RequiresReflowOnSizeAvailable;
  }

  if (aFlags & Flags::RequiresReflowOnFirstFrameCompleteAndLoadEventBlocking) {
    fwfToModify->mFlags |=
        Flags::RequiresReflowOnFirstFrameCompleteAndLoadEventBlocking;

    // If we weren't already blocking onload, do that now.
    if (!(fwfToModify->mFlags & Flags::IsBlockingLoadEvent)) {
      if (TriggerAsyncDecodeAtIntrinsicSize(aRequest)) {
        // If there's no error, and the image has not loaded yet, so we can
        // block onload.
        fwfToModify->mFlags |= Flags::IsBlockingLoadEvent;

        // Block document onload until we either remove the frame in
        // RemoveRequestToFrameMapping or onLoadComplete, or complete a reflow.
        mDocument->BlockOnload();
      }
    }
  }

  // Do some sanity checking to ensure that we only add to one mapping
  // iff we also add to the other mapping.
  DebugOnly<bool> didAddToFrameSet(false);
  DebugOnly<bool> didAddToRequestSet(false);

  // If we weren't already tracking this frame, add it to the frameSet.
  if (!found) {
    frameSet->InsertElementAt(i, fwf);
    didAddToFrameSet = true;
  }

  // Add request to the request set if it wasn't already there.
  i = GetMaybeSortedIndex(*requestSet, aRequest, &found);
  if (!found) {
    requestSet->InsertElementAt(i, aRequest);
    didAddToRequestSet = true;
  }

  MOZ_ASSERT(didAddToFrameSet == didAddToRequestSet,
             "We should only add to one map iff we also add to the other map.");
}

void ImageLoader::RemoveRequestToFrameMapping(imgIRequest* aRequest,
                                              nsIFrame* aFrame) {
#ifdef DEBUG
  {
    nsCOMPtr<imgINotificationObserver> observer;
    aRequest->GetNotificationObserver(getter_AddRefs(observer));
    MOZ_ASSERT(!observer || observer == sImageObserver);
  }
#endif

  if (auto entry = mRequestToFrameMap.Lookup(aRequest)) {
    const auto& frameSet = entry.Data();
    MOZ_ASSERT(frameSet, "This should never be null");

    // Before we remove aFrame from the frameSet, unblock onload if needed.
    bool found;
    uint32_t i = GetMaybeSortedIndex(*frameSet, FrameWithFlags(aFrame), &found,
                                     FrameOnlyComparator());
    if (found) {
      UnblockOnloadIfNeeded(frameSet->ElementAt(i - 1));
      frameSet->RemoveElementAt(i - 1);
    }

    if (frameSet->IsEmpty()) {
      DeregisterImageRequest(aRequest, GetPresContext());
      entry.Remove();
    }
  }
}

void ImageLoader::DeregisterImageRequest(imgIRequest* aRequest,
                                         nsPresContext* aPresContext) {
  mDocument->ImageTracker()->Remove(aRequest);

  if (auto entry = sImages->Lookup(aRequest)) {
    entry.Data()->mImageLoaders.EnsureRemoved(this);
  }

  if (aPresContext) {
    nsLayoutUtils::DeregisterImageRequest(aPresContext, aRequest, nullptr);
  }
}

void ImageLoader::RemoveFrameToRequestMapping(imgIRequest* aRequest,
                                              nsIFrame* aFrame) {
  if (auto entry = mFrameToRequestMap.Lookup(aFrame)) {
    const auto& requestSet = entry.Data();
    MOZ_ASSERT(requestSet, "This should never be null");
    requestSet->RemoveElementSorted(aRequest);
    if (requestSet->IsEmpty()) {
      aFrame->SetHasImageRequest(false);
      entry.Remove();
    }
  }
}

void ImageLoader::DisassociateRequestFromFrame(imgIRequest* aRequest,
                                               nsIFrame* aFrame) {
  MOZ_ASSERT(NS_IsMainThread());
  MOZ_ASSERT(aFrame->HasImageRequest(), "why call me?");

  RemoveRequestToFrameMapping(aRequest, aFrame);
  RemoveFrameToRequestMapping(aRequest, aFrame);
}

void ImageLoader::DropRequestsForFrame(nsIFrame* aFrame) {
  MOZ_ASSERT(NS_IsMainThread());
  MOZ_ASSERT(aFrame->HasImageRequest(), "why call me?");

  UniquePtr<RequestSet> requestSet;
  mFrameToRequestMap.Remove(aFrame, &requestSet);
  aFrame->SetHasImageRequest(false);
  if (MOZ_UNLIKELY(!requestSet)) {
    MOZ_ASSERT_UNREACHABLE("HasImageRequest was lying");
    return;
  }
  for (imgIRequest* request : *requestSet) {
    RemoveRequestToFrameMapping(request, aFrame);
  }
}

void ImageLoader::SetAnimationMode(uint16_t aMode) {
  MOZ_ASSERT(NS_IsMainThread());
  NS_ASSERTION(aMode == imgIContainer::kNormalAnimMode ||
                   aMode == imgIContainer::kDontAnimMode ||
                   aMode == imgIContainer::kLoopOnceAnimMode,
               "Wrong Animation Mode is being set!");

  for (nsISupports* key : mRequestToFrameMap.Keys()) {
    auto* request = static_cast<imgIRequest*>(key);

#ifdef DEBUG
    {
      nsCOMPtr<imgIRequest> debugRequest = request;
      NS_ASSERTION(debugRequest == request, "This is bad");
    }
#endif

    nsCOMPtr<imgIContainer> container;
    request->GetImage(getter_AddRefs(container));
    if (!container) {
      continue;
    }

    // This can fail if the image is in error, and we don't care.
    container->SetAnimationMode(aMode);
  }
}

void ImageLoader::ClearFrames(nsPresContext* aPresContext) {
  MOZ_ASSERT(NS_IsMainThread());

  for (const auto& key : mRequestToFrameMap.Keys()) {
    auto* request = static_cast<imgIRequest*>(key);

#ifdef DEBUG
    {
      nsCOMPtr<imgIRequest> debugRequest = request;
      NS_ASSERTION(debugRequest == request, "This is bad");
    }
#endif

    DeregisterImageRequest(request, aPresContext);
  }

  mRequestToFrameMap.Clear();
  mFrameToRequestMap.Clear();
}

static CORSMode EffectiveCorsMode(nsIURI* aURI,
                                  const StyleComputedImageUrl& aImage) {
  MOZ_ASSERT(aURI);
  StyleCorsMode mode = aImage.CorsMode();
  if (mode == StyleCorsMode::None) {
    return CORSMode::CORS_NONE;
  }
  MOZ_ASSERT(mode == StyleCorsMode::Anonymous);
  if (aURI->SchemeIs("resource")) {
    return CORSMode::CORS_NONE;
  }
  return CORSMode::CORS_ANONYMOUS;
}

/* static */
already_AddRefed<imgRequestProxy> ImageLoader::LoadImage(
    const StyleComputedImageUrl& aImage, Document& aDocument) {
  MOZ_ASSERT(NS_IsMainThread());
  nsIURI* uri = aImage.GetURI();
  if (!uri) {
    return nullptr;
  }

  if (aImage.HasRef()) {
    bool isEqualExceptRef = false;
    nsIURI* docURI = aDocument.GetDocumentURI();
    if (NS_SUCCEEDED(uri->EqualsExceptRef(docURI, &isEqualExceptRef)) &&
        isEqualExceptRef) {
      // Prevent loading an internal resource.
      return nullptr;
    }
  }

  int32_t loadFlags =
      nsIRequest::LOAD_NORMAL |
      nsContentUtils::CORSModeToLoadImageFlags(EffectiveCorsMode(uri, aImage));

  const URLExtraData& data = aImage.ExtraData();

  RefPtr<imgRequestProxy> request;
  nsresult rv = nsContentUtils::LoadImage(
      uri, &aDocument, &aDocument, data.Principal(), 0, data.ReferrerInfo(),
      sImageObserver, loadFlags, u"css"_ns, getter_AddRefs(request));

  if (NS_FAILED(rv) || !request) {
    return nullptr;
  }

  // This image could be shared across documents, so its load cannot be
  // canceled, see bug 1800979.
  request->SetCancelable(false);
  sImages->GetOrInsertNew(request);
  return request.forget();
}

void ImageLoader::UnloadImage(imgRequestProxy* aImage) {
  MOZ_ASSERT(NS_IsMainThread());
  MOZ_ASSERT(aImage);

  if (MOZ_UNLIKELY(!sImages)) {
    return;  // Shutdown() takes care of it.
  }

  auto lookup = sImages->Lookup(aImage);
  MOZ_DIAGNOSTIC_ASSERT(lookup, "Unregistered image?");
  if (MOZ_UNLIKELY(!lookup)) {
    return;
  }

  if (MOZ_UNLIKELY(--lookup.Data()->mSharedCount)) {
    // Someone else still cares about this image.
    return;
  }

  // Now we want to really cancel the request.
  aImage->SetCancelable(true);
  aImage->CancelAndForgetObserver(NS_BINDING_ABORTED);
  MOZ_DIAGNOSTIC_ASSERT(lookup.Data()->mImageLoaders.IsEmpty(),
                        "Shouldn't be keeping references to any loader "
                        "by now");
  lookup.Remove();
}

void ImageLoader::NoteSharedLoad(imgRequestProxy* aImage) {
  MOZ_ASSERT(NS_IsMainThread());
  MOZ_ASSERT(aImage);

  auto lookup = sImages->Lookup(aImage);
  MOZ_DIAGNOSTIC_ASSERT(lookup, "Unregistered image?");
  if (MOZ_UNLIKELY(!lookup)) {
    return;
  }

  lookup.Data()->mSharedCount++;
}

nsPresContext* ImageLoader::GetPresContext() {
  if (!mDocument) {
    return nullptr;
  }

  return mDocument->GetPresContext();
}

static bool IsRenderNoImages(uint32_t aDisplayItemKey) {
  DisplayItemType type = GetDisplayItemTypeFromKey(aDisplayItemKey);
  uint8_t flags = GetDisplayItemFlagsForType(type);
  return flags & TYPE_RENDERS_NO_IMAGES;
}

static void InvalidateImages(nsIFrame* aFrame, imgIRequest* aRequest,
                             bool aForcePaint) {
  if (!aFrame->StyleVisibility()->IsVisible()) {
    return;
  }

  if (aFrame->IsFrameOfType(nsIFrame::eTablePart)) {
    // Tables don't necessarily build border/background display items
    // for the individual table part frames, so IterateRetainedDataFor
    // might not find the right display item.
    return aFrame->InvalidateFrame();
  }

  if (aFrame->IsPrimaryFrameOfRootOrBodyElement()) {
    if (auto* canvas = aFrame->PresShell()->GetCanvasFrame()) {
      // Try to invalidate the canvas too, in the probable case the background
      // was propagated to it.
      InvalidateImages(canvas, aRequest, aForcePaint);
    }
  }

  bool invalidateFrame = aForcePaint;

  if (auto userDataTable =
          aFrame->GetProperty(layers::WebRenderUserDataProperty::Key())) {
    for (RefPtr<layers::WebRenderUserData> data : userDataTable->Values()) {
      switch (data->GetType()) {
        case layers::WebRenderUserData::UserDataType::eFallback:
          if (!IsRenderNoImages(data->GetDisplayItemKey())) {
            static_cast<layers::WebRenderFallbackData*>(data.get())
                ->SetInvalid(true);
          }
          // XXX: handle Blob data
          invalidateFrame = true;
          break;
        case layers::WebRenderUserData::UserDataType::eMask:
          static_cast<layers::WebRenderMaskData*>(data.get())->Invalidate();
          invalidateFrame = true;
          break;
        case layers::WebRenderUserData::UserDataType::eImageProvider:
          if (static_cast<layers::WebRenderImageProviderData*>(data.get())
                  ->Invalidate(aRequest->GetProviderId())) {
            break;
          }
          [[fallthrough]];
        default:
          invalidateFrame = true;
          break;
      }
    }
  }

  // Update ancestor rendering observers (-moz-element etc)
  //
  // NOTE: We need to do this even if invalidateFrame is false, see bug 1114526.
  {
    nsIFrame* f = aFrame;
    while (f && !f->HasAnyStateBits(NS_FRAME_DESCENDANT_NEEDS_PAINT)) {
      SVGObserverUtils::InvalidateDirectRenderingObservers(f);
      f = nsLayoutUtils::GetCrossDocParentFrameInProcess(f);
    }
  }

  if (invalidateFrame) {
    aFrame->SchedulePaint();
  }
}

void ImageLoader::UnblockOnloadIfNeeded(FrameWithFlags& aFwf) {
  if (aFwf.mFlags & Flags::IsBlockingLoadEvent) {
    mDocument->UnblockOnload(false);
    aFwf.mFlags &= ~Flags::IsBlockingLoadEvent;
  }
}

void ImageLoader::UnblockOnloadIfNeeded(nsIFrame* aFrame,
                                        imgIRequest* aRequest) {
  MOZ_ASSERT(aFrame);
  MOZ_ASSERT(aRequest);

  FrameSet* frameSet = mRequestToFrameMap.Get(aRequest);
  if (!frameSet) {
    return;
  }

  size_t i =
      frameSet->BinaryIndexOf(FrameWithFlags(aFrame), FrameOnlyComparator());
  if (i != FrameSet::NoIndex) {
    UnblockOnloadIfNeeded(frameSet->ElementAt(i));
  }
}

// This callback is used to unblock document onload after a reflow
// triggered from an image load.
struct ImageLoader::ImageReflowCallback final : public nsIReflowCallback {
  RefPtr<ImageLoader> mLoader;
  WeakFrame mFrame;
  nsCOMPtr<imgIRequest> const mRequest;

  ImageReflowCallback(ImageLoader* aLoader, nsIFrame* aFrame,
                      imgIRequest* aRequest)
      : mLoader(aLoader), mFrame(aFrame), mRequest(aRequest) {}

  bool ReflowFinished() override;
  void ReflowCallbackCanceled() override;
};

bool ImageLoader::ImageReflowCallback::ReflowFinished() {
  // Check that the frame is still valid. If it isn't, then onload was
  // unblocked when the frame was removed from the FrameSet in
  // RemoveRequestToFrameMapping.
  if (mFrame.IsAlive()) {
    mLoader->UnblockOnloadIfNeeded(mFrame, mRequest);
  }

  // Get rid of this callback object.
  delete this;

  // We don't need to trigger layout.
  return false;
}

void ImageLoader::ImageReflowCallback::ReflowCallbackCanceled() {
  // Check that the frame is still valid. If it isn't, then onload was
  // unblocked when the frame was removed from the FrameSet in
  // RemoveRequestToFrameMapping.
  if (mFrame.IsAlive()) {
    mLoader->UnblockOnloadIfNeeded(mFrame, mRequest);
  }

  // Get rid of this callback object.
  delete this;
}

void GlobalImageObserver::Notify(imgIRequest* aRequest, int32_t aType,
                                 const nsIntRect* aData) {
  auto entry = sImages->Lookup(aRequest);
  MOZ_DIAGNOSTIC_ASSERT(entry);
  if (MOZ_UNLIKELY(!entry)) {
    return;
  }

  const auto loadersToNotify =
      ToTArray<nsTArray<RefPtr<ImageLoader>>>(entry.Data()->mImageLoaders);
  for (const auto& loader : loadersToNotify) {
    loader->Notify(aRequest, aType, aData);
  }
}

void ImageLoader::Notify(imgIRequest* aRequest, int32_t aType,
                         const nsIntRect* aData) {
  nsCString uriString;
  if (profiler_is_active()) {
    nsCOMPtr<nsIURI> uri;
    aRequest->GetFinalURI(getter_AddRefs(uri));
    if (uri) {
      uri->GetSpec(uriString);
    }
  }

  AUTO_PROFILER_LABEL_DYNAMIC_CSTR("ImageLoader::Notify", OTHER,
                                   uriString.get());

  if (aType == imgINotificationObserver::SIZE_AVAILABLE) {
    nsCOMPtr<imgIContainer> image;
    aRequest->GetImage(getter_AddRefs(image));
    return OnSizeAvailable(aRequest, image);
  }

  if (aType == imgINotificationObserver::IS_ANIMATED) {
    return OnImageIsAnimated(aRequest);
  }

  if (aType == imgINotificationObserver::FRAME_COMPLETE) {
    return OnFrameComplete(aRequest);
  }

  if (aType == imgINotificationObserver::FRAME_UPDATE) {
    return OnFrameUpdate(aRequest);
  }

  if (aType == imgINotificationObserver::DECODE_COMPLETE) {
    nsCOMPtr<imgIContainer> image;
    aRequest->GetImage(getter_AddRefs(image));
    if (image && mDocument) {
      image->PropagateUseCounters(mDocument);
    }
  }

  if (aType == imgINotificationObserver::LOAD_COMPLETE) {
    return OnLoadComplete(aRequest);
  }
}

void ImageLoader::OnSizeAvailable(imgIRequest* aRequest,
                                  imgIContainer* aImage) {
  nsPresContext* presContext = GetPresContext();
  if (!presContext) {
    return;
  }

  aImage->SetAnimationMode(presContext->ImageAnimationMode());

  FrameSet* frameSet = mRequestToFrameMap.Get(aRequest);
  if (!frameSet) {
    return;
  }

  for (const FrameWithFlags& fwf : *frameSet) {
    if (fwf.mFlags & Flags::RequiresReflowOnSizeAvailable) {
      fwf.mFrame->PresShell()->FrameNeedsReflow(
          fwf.mFrame, IntrinsicDirty::FrameAncestorsAndDescendants,
          NS_FRAME_IS_DIRTY);
    }
  }
}

void ImageLoader::OnImageIsAnimated(imgIRequest* aRequest) {
  if (!mDocument) {
    return;
  }

  FrameSet* frameSet = mRequestToFrameMap.Get(aRequest);
  if (!frameSet) {
    return;
  }

  // Register with the refresh driver now that we are aware that
  // we are animated.
  nsPresContext* presContext = GetPresContext();
  if (presContext) {
    nsLayoutUtils::RegisterImageRequest(presContext, aRequest, nullptr);
  }
}

void ImageLoader::OnFrameComplete(imgIRequest* aRequest) {
  ImageFrameChanged(aRequest, /* aFirstFrame = */ true);
}

void ImageLoader::OnFrameUpdate(imgIRequest* aRequest) {
  ImageFrameChanged(aRequest, /* aFirstFrame = */ false);
}

void ImageLoader::ImageFrameChanged(imgIRequest* aRequest, bool aFirstFrame) {
  if (!mDocument) {
    return;
  }

  FrameSet* frameSet = mRequestToFrameMap.Get(aRequest);
  if (!frameSet) {
    return;
  }

  for (FrameWithFlags& fwf : *frameSet) {
    // Since we just finished decoding a frame, we always want to paint, in
    // case we're now able to paint an image that we couldn't paint before
    // (and hence that we don't have retained data for).
    const bool forceRepaint = aFirstFrame;
    InvalidateImages(fwf.mFrame, aRequest, forceRepaint);
    if (!aFirstFrame) {
      // We don't reflow / try to unblock onload for subsequent frame updates.
      continue;
    }
    if (fwf.mFlags &
        Flags::RequiresReflowOnFirstFrameCompleteAndLoadEventBlocking) {
      // Tell the container of the frame to reflow because the image request
      // has finished decoding its first frame.
      // FIXME(emilio): Why requesting reflow on the _parent_?
      nsIFrame* parent = fwf.mFrame->GetInFlowParent();
      parent->PresShell()->FrameNeedsReflow(
          parent, IntrinsicDirty::FrameAncestorsAndDescendants,
          NS_FRAME_IS_DIRTY);
      // If we need to also potentially unblock onload, do it once reflow is
      // done, with a reflow callback.
      if (fwf.mFlags & Flags::IsBlockingLoadEvent) {
        auto* unblocker = new ImageReflowCallback(this, fwf.mFrame, aRequest);
        parent->PresShell()->PostReflowCallback(unblocker);
      }
    }
  }
}

void ImageLoader::OnLoadComplete(imgIRequest* aRequest) {
  if (!mDocument) {
    return;
  }

  uint32_t status = 0;
  if (NS_FAILED(aRequest->GetImageStatus(&status))) {
    return;
  }

  FrameSet* frameSet = mRequestToFrameMap.Get(aRequest);
  if (!frameSet) {
    return;
  }

  for (FrameWithFlags& fwf : *frameSet) {
    if (status & imgIRequest::STATUS_ERROR) {
      // Check if aRequest has an error state. If it does, we need to unblock
      // Document onload for all the frames associated with this request that
      // have blocked onload. This is what happens in a CORS mode violation, and
      // may happen during other network events.
      UnblockOnloadIfNeeded(fwf);
    }
    if (fwf.mFrame->StyleVisibility()->IsVisible()) {
      fwf.mFrame->SchedulePaint();
    }
  }
}

}  // namespace mozilla::css