Bug 1263829 - Part 2: Don't apply opacity in PaintFramesWithEffects if we created an nsDisplayOpacity. r=jwatt

layout/base/nsDisplayList.cpp

@@ -6572,9 +6572,11 @@ nsCharClipDisplayItem::ComputeInvalidationRegion(nsDisplayListBuilder* aBuilder,
 }
 
 nsDisplaySVGEffects::nsDisplaySVGEffects(nsDisplayListBuilder* aBuilder,
-                                         nsIFrame* aFrame, nsDisplayList* aList)
-    : nsDisplayWrapList(aBuilder, aFrame, aList),
-      mEffectsBounds(aFrame->GetVisualOverflowRectRelativeToSelf())
+                                         nsIFrame* aFrame, nsDisplayList* aList,
+                                         bool aOpacityItemCreated)
+  : nsDisplayWrapList(aBuilder, aFrame, aList)
+  , mEffectsBounds(aFrame->GetVisualOverflowRectRelativeToSelf())
+  , mOpacityItemCreated(aOpacityItemCreated)
 {
   MOZ_COUNT_CTOR(nsDisplaySVGEffects);
 }
@@ -6638,7 +6640,7 @@ nsDisplaySVGEffects::PaintAsLayer(nsDisplayListBuilder* aBuilder,
   nsSVGIntegrationUtils::PaintFramesParams params(*aCtx->ThebesContext(),
                                                   mFrame,  mVisibleRect,
                                                   borderArea, aBuilder,
-                                                  aManager);
+                                                  aManager, mOpacityItemCreated);
 
   nsSVGIntegrationUtils::PaintFramesWithEffects(params);
 }

layout/base/nsDisplayList.h

@@ -3788,7 +3788,7 @@ private:
 class nsDisplaySVGEffects : public nsDisplayWrapList {
 public:
   nsDisplaySVGEffects(nsDisplayListBuilder* aBuilder, nsIFrame* aFrame,
-                      nsDisplayList* aList);
+                      nsDisplayList* aList, bool aOpacityItemCreated);
 #ifdef NS_BUILD_REFCNT_LOGGING
   virtual ~nsDisplaySVGEffects();
 #endif
@@ -3842,6 +3842,9 @@ public:
 private:
   // relative to mFrame
   nsRect mEffectsBounds;
+  // True if the caller also created an nsDisplayOpacity item, and we should tell
+  // PaintFramesWithEffects that it doesn't need to handle opacity itself.
+  bool mOpacityItemCreated;
 };
 
 /* A display item that applies a transformation to all of its descendant

layout/generic/nsFrame.cpp

@@ -2285,7 +2285,11 @@ nsIFrame::BuildDisplayListForStackingContext(nsDisplayListBuilder* aBuilder,
     aBuilder->EnterSVGEffectsContents(&hoistedScrollInfoItemsStorage);
   }
 
-  bool useOpacity = HasVisualOpacity() && !nsSVGUtils::CanOptimizeOpacity(this) && !usingSVGEffects;
+  // We build an opacity item if it's not going to be drawn by SVG content, or SVG effects.
+  // SVG effects won't handle the opacity if we want an active layer (for async animations),
+  // see nsSVGIntegrationsUtils::PaintFramesWithEffects.
+  bool useOpacity = HasVisualOpacity() && !nsSVGUtils::CanOptimizeOpacity(this) &&
+                    (!usingSVGEffects || nsDisplayOpacity::NeedsActiveLayer(aBuilder, this));
   bool useBlendMode = effects->mMixBlendMode != NS_STYLE_BLEND_NORMAL;
   bool useStickyPosition = disp->mPosition == NS_STYLE_POSITION_STICKY &&
     IsScrollFrameActive(aBuilder,
@@ -2456,7 +2460,7 @@ nsIFrame::BuildDisplayListForStackingContext(nsDisplayListBuilder* aBuilder,
     buildingDisplayList.SetDirtyRect(dirtyRectOutsideSVGEffects);
     /* List now emptied, so add the new list to the top. */
     resultList.AppendNewToTop(
-        new (aBuilder) nsDisplaySVGEffects(aBuilder, this, &resultList));
+        new (aBuilder) nsDisplaySVGEffects(aBuilder, this, &resultList, useOpacity));
     // Also add the hoisted scroll info items. We need those for APZ scrolling
     // because nsDisplaySVGEffects items can't build active layers.
     aBuilder->ExitSVGEffectsContents();

layout/svg/nsSVGIntegrationUtils.cpp

@@ -564,9 +564,12 @@ nsSVGIntegrationUtils::PaintFramesWithEffects(const PaintFramesParams& aParams)
     return;
   }
   if (opacity != 1.0f &&
-      hasSVGLayout && nsSVGUtils::CanOptimizeOpacity(frame)) {
+      (nsSVGUtils::CanOptimizeOpacity(frame) ||
+       aParams.callerPaintsOpacity)) {
     opacity = 1.0f;
   }
+  MOZ_ASSERT(!nsSVGUtils::CanOptimizeOpacity(frame) || !aParams.callerPaintsOpacity,
+             "How can we be optimizing the opacity into the svg as well as having the caller paint it?");
 
   /* Properties are added lazily and may have been removed by a restyle,
      so make sure all applicable ones are set again. */

layout/svg/nsSVGIntegrationUtils.h

@@ -130,14 +130,16 @@ public:
     const nsRect& borderArea;
     nsDisplayListBuilder* builder;
     mozilla::layers::LayerManager* layerManager;
+    bool callerPaintsOpacity;
     explicit PaintFramesParams(gfxContext& aCtx, nsIFrame* aFrame,
                                const nsRect& aDirtyRect,
                                const nsRect& aBorderArea,
                                nsDisplayListBuilder* aBuilder,
-                               mozilla::layers::LayerManager* aLayerManager)
+                               mozilla::layers::LayerManager* aLayerManager,
+                               bool aCallerPaintsOpacity)
       : ctx(aCtx), frame(aFrame), dirtyRect(aDirtyRect),
         borderArea(aBorderArea), builder(aBuilder),
-        layerManager(aLayerManager)
+        layerManager(aLayerManager), callerPaintsOpacity(aCallerPaintsOpacity)
     { }
   };