Bug 1526970 - Part 3: Remove nsPaintedDisplayItem::mDisplayItemData r=mattwoodrow

Depends on D106164

Differential Revision: https://phabricator.services.mozilla.com/D106165

layout/painting/FrameLayerBuilder.cpp

@@ -386,14 +386,8 @@ void DisplayItemData::BeginUpdate(Layer* aLayer, LayerState aState,
   mLayerState = aState;
   mUsed = true;
 
-  if (aLayer->AsPaintedLayer()) {
-    if (aItem != mItem) {
-      aItem->SetDisplayItemData(this, aLayer->Manager());
-    } else {
-      MOZ_ASSERT(aItem->GetDisplayItemData() == this);
-    }
-    mReusedItem = aIsReused;
-  }
+  mItem = aItem;
+  mReusedItem = aIsReused;
 
   if (!aItem) {
     return;
@@ -436,11 +430,6 @@ static const nsIFrame* sDestroyedFrame = nullptr;
 DisplayItemData::~DisplayItemData() {
   MOZ_COUNT_DTOR(DisplayItemData);
 
-  if (mItem) {
-    MOZ_ASSERT(mItem->GetDisplayItemData() == this);
-    mItem->SetDisplayItemData(nullptr, nullptr);
-  }
-
   for (nsIFrame* frame : mFrameList) {
     if (frame == sDestroyedFrame) {
       continue;
@@ -3905,12 +3894,8 @@ void PaintedLayerData::Accumulate(ContainerState* aState, nsDisplayItem* aItem,
   bool clipMatches =
       (oldClip == mItemClip) || (oldClip && *oldClip == *mItemClip);
 
-  DisplayItemData* currentData =
-      isMerged ? nullptr : item->GetDisplayItemData();
-
   DisplayItemData* oldData = aState->mLayerBuilder->GetOldLayerForFrame(
-      item->Frame(), item->GetPerFrameKey(), currentData,
-      item->GetDisplayItemDataLayerManager());
+      item->Frame(), item->GetPerFrameKey());
 
   mAssignedDisplayItems.emplace_back(item, aLayerState, oldData, aContentRect,
                                      aType, hasOpacity, aTransform, isMerged);
@@ -5411,12 +5396,6 @@ void FrameLayerBuilder::AddPaintedDisplayItem(PaintedLayerData* aLayerData,
       data->BeginUpdate(layer, aItem.mLayerState, aItem.mItem, aItem.mReused,
                         aItem.mMerged);
     } else {
-      if (data && data->mUsed) {
-        // If the DID has already been used (by a previously merged frame,
-        // which is not merged this paint) we must create a new DID for the
-        // item.
-        aItem.mItem->SetDisplayItemData(nullptr, nullptr);
-      }
       data = StoreDataForFrame(aItem.mItem, layer, aItem.mLayerState, nullptr);
     }
     data->mInactiveManager = aItem.mInactiveLayerData

layout/painting/FrameLayerBuilder.h

@@ -107,8 +107,6 @@ class DisplayItemData final {
   const DisplayItemClip& GetClip() const { return mClip; }
   void Invalidate() { mIsInvalid = true; }
   void NotifyRemoved();
-  void SetItem(nsPaintedDisplayItem* aItem) { mItem = aItem; }
-  nsPaintedDisplayItem* GetItem() const { return mItem; }
   nsIFrame* FirstFrame() const { return mFrameList[0]; }
   layers::BasicLayerManager* InactiveManager() const {
     return mInactiveManager;

layout/painting/nsDisplayList.cpp

@@ -156,24 +156,6 @@ bool ShouldBuildItemForEvents(const DisplayItemType aType) {
          (GetDisplayItemFlagsForType(aType) & TYPE_IS_CONTAINER);
 }
 
-void UpdateDisplayItemData(nsPaintedDisplayItem* aItem) {
-  auto* array = aItem->Frame()->DisplayItemData();
-  if (!array) {
-    return;
-  }
-
-  for (auto* did : *array) {
-    if (did->GetDisplayItemKey() == aItem->GetPerFrameKey() &&
-        did->GetLayer()->AsPaintedLayer()) {
-      if (!did->HasMergedFrames()) {
-        aItem->SetDisplayItemData(did, did->GetLayer()->Manager());
-      }
-
-      return;
-    }
-  }
-}
-
 static bool ItemTypeSupportsHitTesting(const DisplayItemType aType) {
   switch (aType) {
     case DisplayItemType::TYPE_BACKGROUND:

layout/painting/nsDisplayList.h

@@ -2092,11 +2092,6 @@ void AssertUniqueItem(nsDisplayItem* aItem);
  */
 bool ShouldBuildItemForEvents(const DisplayItemType aType);
 
-/**
- * Updates the item DisplayItemData if needed.
- */
-void UpdateDisplayItemData(nsPaintedDisplayItem* aItem);
-
 /**
  * Initializes the hit test information of |aItem| if the item type supports it.
  */
@@ -2130,7 +2125,6 @@ MOZ_ALWAYS_INLINE T* MakeDisplayItemWithIndex(nsDisplayListBuilder* aBuilder,
 
   nsPaintedDisplayItem* paintedItem = item->AsPaintedDisplayItem();
   if (paintedItem) {
-    UpdateDisplayItemData(paintedItem);
     InitializeHitTestInfo(aBuilder, paintedItem, type);
   }
 
@@ -3183,30 +3177,6 @@ class nsPaintedDisplayItem : public nsDisplayItem {
     return this;
   }
 
-  ~nsPaintedDisplayItem() override { SetDisplayItemData(nullptr, nullptr); }
-
-  void SetDisplayItemData(mozilla::DisplayItemData* aDID,
-                          mozilla::layers::LayerManager* aLayerManager) {
-    if (mDisplayItemData) {
-      MOZ_ASSERT(!mDisplayItemData->GetItem() ||
-                 mDisplayItemData->GetItem() == this);
-      mDisplayItemData->SetItem(nullptr);
-    }
-    if (aDID) {
-      if (aDID->GetItem()) {
-        aDID->GetItem()->SetDisplayItemData(nullptr, nullptr);
-      }
-      aDID->SetItem(this);
-    }
-    mDisplayItemData = aDID;
-    mDisplayItemDataLayerManager = aLayerManager;
-  }
-
-  mozilla::DisplayItemData* GetDisplayItemData() { return mDisplayItemData; }
-  mozilla::layers::LayerManager* GetDisplayItemDataLayerManager() {
-    return mDisplayItemDataLayerManager;
-  }
-
   /**
    * Stores the given opacity value to be applied when drawing. It is an error
    * to call this if CanApplyOpacity returned false.
@@ -3299,13 +3269,9 @@ class nsPaintedDisplayItem : public nsDisplayItem {
                        const nsPaintedDisplayItem& aOther)
       : nsDisplayItem(aBuilder, aOther), mHitTestInfo(aOther.mHitTestInfo) {}
 
- private:
-  mozilla::DisplayItemData* mDisplayItemData = nullptr;
-  mozilla::layers::LayerManager* mDisplayItemDataLayerManager = nullptr;
-  mozilla::Maybe<uint16_t> mCacheIndex;
-
  protected:
   mozilla::HitTestInfo mHitTestInfo;
+  mozilla::Maybe<uint16_t> mCacheIndex;
 };
 
 /**