Backed out changeset e8ffcf4b8e22 (bug 846901)

layout/base/FrameLayerBuilder.cpp

@@ -2136,8 +2136,7 @@ ContainerState::ProcessDisplayItems(const nsDisplayList& aList,
       // Note that items without their own layers can't be skipped this
       // way, since their ThebesLayer may decide it wants to draw them
       // into its buffer even if they're currently covered.
-      if (itemVisibleRect.IsEmpty() &&
-          !item->ShouldBuildLayerEvenIfInvisible(mBuilder)) {
+      if (itemVisibleRect.IsEmpty() && layerState != LAYER_ACTIVE_EMPTY) {
         continue;
       }
 
@@ -2193,9 +2192,7 @@ ContainerState::ProcessDisplayItems(const nsDisplayList& aList,
         data->mDrawAboveRegion.SimplifyOutward(4);
       }
       itemVisibleRect.MoveBy(mParameters.mOffset);
-      if (!nsDisplayTransform::IsLayerPrerendered(ownLayer)) {
-        RestrictVisibleRegionForLayer(ownLayer, itemVisibleRect);
-      }
+      RestrictVisibleRegionForLayer(ownLayer, itemVisibleRect);
 
       // rounded rectangle clipping using mask layers
       // (must be done after visible rect is set on layer)

layout/base/nsDisplayList.cpp

@@ -570,24 +570,12 @@ void nsDisplayListBuilder::MarkOutOfFlowFrameForDisplay(nsIFrame* aDirtyFrame,
   nsRect dirty = aDirtyRect - aFrame->GetOffsetTo(aDirtyFrame);
   nsRect overflowRect = aFrame->GetVisualOverflowRect();
 
-  if (aFrame->IsTransformed() &&
-      nsLayoutUtils::HasAnimationsForCompositor(aFrame->GetContent(),
-                                                eCSSProperty_transform)) {
-   /**
-    * Add a fuzz factor to the overflow rectangle so that elements only just
-    * out of view are pulled into the display list, so they can be
-    * prerendered if necessary.
-    */
-    overflowRect.Inflate(nsPresContext::CSSPixelsToAppUnits(32));
-  }
-
   if (mHasDisplayPort && IsFixedFrame(aFrame)) {
     dirty = overflowRect;
   }
 
   if (!dirty.IntersectRect(dirty, overflowRect))
     return;
-
   aFrame->Properties().Set(nsDisplayListBuilder::OutOfFlowDirtyRectProperty(),
                            new nsRect(dirty));
 
@@ -3903,13 +3891,7 @@ nsDisplayTransform::ShouldPrerenderTransformedContent(nsDisplayListBuilder* aBui
                                                       nsIFrame* aFrame,
                                                       bool aLogAnimations)
 {
-  // Elements whose transform has been modified recently, or which
-  // have a compositor-animated transform, can be prerendered. An element
-  // might have only just had its transform animated in which case
-  // nsChangeHint_UpdateTransformLayer will not be present yet.
-  if (!aFrame->AreLayersMarkedActive(nsChangeHint_UpdateTransformLayer) &&
-      !nsLayoutUtils::HasAnimationsForCompositor(aFrame->GetContent(),
-                                                 eCSSProperty_transform)) {
+  if (!aFrame->AreLayersMarkedActive(nsChangeHint_UpdateTransformLayer)) {
     if (aLogAnimations) {
       nsCString message;
       message.AppendLiteral("Performance warning: Async animation disabled because frame was not marked active for transform animation");
@@ -3996,12 +3978,6 @@ nsDisplayTransform::GetTransform(float aAppUnitsPerPixel)
   return mTransform;
 }
 
-bool
-nsDisplayTransform::ShouldBuildLayerEvenIfInvisible(nsDisplayListBuilder* aBuilder)
-{
-  return ShouldPrerenderTransformedContent(aBuilder, mFrame, false);
-}
-
 already_AddRefed<Layer> nsDisplayTransform::BuildLayer(nsDisplayListBuilder *aBuilder,
                                                        LayerManager *aManager,
                                                        const ContainerParameters& aContainerParameters)

layout/base/nsDisplayList.h

@@ -966,12 +966,6 @@ public:
                                    LayerManager* aManager,
                                    const ContainerParameters& aParameters)
   { return mozilla::LAYER_NONE; }
-  /**
-   * Return true to indicate the layer should be constructed even if it's
-   * completely invisible.
-   */
-  virtual bool ShouldBuildLayerEvenIfInvisible(nsDisplayListBuilder* aBuilder)
-  { return false; }
   /**
    * Actually paint this item to some rendering context.
    * Content outside mVisibleRect need not be painted.
@@ -2539,8 +2533,7 @@ public:
   virtual LayerState GetLayerState(nsDisplayListBuilder* aBuilder,
                                    LayerManager* aManager,
                                    const ContainerParameters& aParameters) MOZ_OVERRIDE;
-  virtual bool ShouldBuildLayerEvenIfInvisible(nsDisplayListBuilder* aBuilder) MOZ_OVERRIDE
-  { return true; }
+
   virtual bool TryMerge(nsDisplayListBuilder* aBuilder,
                           nsDisplayItem* aItem) MOZ_OVERRIDE;
 
@@ -2796,7 +2789,6 @@ public:
   virtual already_AddRefed<Layer> BuildLayer(nsDisplayListBuilder* aBuilder,
                                              LayerManager* aManager,
                                              const ContainerParameters& aContainerParameters) MOZ_OVERRIDE;
-  virtual bool ShouldBuildLayerEvenIfInvisible(nsDisplayListBuilder* aBuilder) MOZ_OVERRIDE;
   virtual bool ComputeVisibility(nsDisplayListBuilder *aBuilder,
                                    nsRegion *aVisibleRegion,
                                    const nsRect& aAllowVisibleRegionExpansion) MOZ_OVERRIDE;
@@ -2948,11 +2940,6 @@ public:
                                                 bool aLogAnimations = false);
   bool CanUseAsyncAnimations(nsDisplayListBuilder* aBuilder) MOZ_OVERRIDE;
 
-  static bool IsLayerPrerendered(Layer* aLayer)
-  {
-    return aLayer->HasUserData(nsIFrame::LayerIsPrerenderedDataKey());
-  }
-
 private:
   static gfx3DMatrix GetResultingTransformMatrixInternal(const FrameTransformProperties& aProperties,
                                                          const nsPoint& aOrigin,

layout/base/nsLayoutDebugger.cpp

@@ -130,6 +130,10 @@ PrintDisplayListTo(nsDisplayListBuilder* aBuilder, const nsDisplayList& aList,
   }
 
   for (nsDisplayItem* i = aList.GetBottom(); i != nullptr; i = i->GetAbove()) {
+#ifdef DEBUG
+    if (aList.DidComputeVisibility() && i->GetVisibleRect().IsEmpty())
+      continue;
+#endif
     if (aDumpHtml) {
       fprintf(aOutput, "<li>");
     } else {