[SPv2] Fix logic for blending effect nodes due to non-isolated children of SVG.

third_party/WebKit/Source/core/paint/PaintPropertyTreeBuilder.cpp

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "core/paint/PaintPropertyTreeBuilder.h"
 
 #include <memory>
 #include "core/dom/DOMNodeIds.h"
 #include "core/frame/FrameView.h"
 #include "core/frame/LocalFrame.h"
@@ skipping 464 matching lines @@
   }
 
   // TODO(trchen): Can't omit effect node if we have 3D children.
   if (object.needsPaintPropertyUpdate() || context.forceSubtreeUpdate) {
     const ClipPaintPropertyNode* outputClip = context.inputClipOfCurrentEffect;
 
     bool effectNodeNeeded = false;
 
     // Can't omit effect node if we have paint children with exotic blending.
     if (object.isSVG()) {
-      // Yes, including LayoutSVGRoot, because SVG layout objects don't create
-      // PaintLayer so PaintLayer::hasNonIsolatedDescendantWithBlendMode()
-      // doesn't catch SVG descendants.
-      if (SVGLayoutSupport::isIsolationRequired(&object))
+      // This handles SVGRoot objects which have PaintLayers.
+      if (object.isSVGRoot() && object.hasNonIsolatedBlendingDescendants())

[trchen, 2017/03/31 21:33:35]

if (isCSSIsolatedGroup && object.hasNonIsolatedBlendingDescendants())

+        effectNodeNeeded = true;
+      else if (SVGLayoutSupport::isIsolationRequired(&object))
         effectNodeNeeded = true;
     } else if (PaintLayer* layer = toLayoutBoxModelObject(object).layer()) {
       if (layer->hasNonIsolatedDescendantWithBlendMode())
         effectNodeNeeded = true;
     }
 
     SkBlendMode blendMode = object.isBlendingAllowed()
                                 ? WebCoreCompositeToSkiaComposite(
                                       CompositeSourceOver, style.blendMode())
                                 : SkBlendMode::kSrcOver;
@@ skipping 633 matching lines @@
   updateOverflowClip(object, context);
   updatePerspective(object, context);
   updateSvgLocalToBorderBoxTransform(object, context);
   updateScrollAndScrollTranslation(object, context);
   updateOutOfFlowContext(object, context);
 
   context.forceSubtreeUpdate |= object.subtreeNeedsPaintPropertyUpdate();
 }
 
 }  // namespace blink