[CSS Blending] SVG overlapping elements within a group don't blend together.

Source/core/rendering/svg/SVGRenderingContext.cpp

 /*
  * Copyright (C) 2007, 2008 Rob Buis <buis@kde.org>
  * Copyright (C) 2007 Nikolas Zimmermann <zimmermann@kde.org>
  * Copyright (C) 2007 Eric Seidel <eric@webkit.org>
  * Copyright (C) 2009 Google, Inc.  All rights reserved.
  * Copyright (C) 2009 Dirk Schulze <krit@webkit.org>
  * Copyright (C) Research In Motion Limited 2009-2010. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
@@ skipping 101 matching lines @@
     ASSERT(svgStyle);
 
     // Setup transparency layers before setting up SVG resources!
     bool isRenderingMask = isRenderingMaskImage(m_object);
     float opacity = isRenderingMask ? 1 : style->opacity();
     bool hasBlendMode = style->hasBlendMode() && !isRenderingMask;
 
     if (opacity < 1 || hasBlendMode || style->hasIsolation()) {
         FloatRect repaintRect = m_object->repaintRectInLocalCoordinates();
         m_paintInfo->context->clip(repaintRect);
+
         if (hasBlendMode) {
             if (!(m_renderingFlags & RestoreGraphicsContext)) {
                 m_paintInfo->context->save();
                 m_renderingFlags |= RestoreGraphicsContext;
             }
             m_paintInfo->context->setCompositeOperation(CompositeSourceOver, style->blendMode());
         }
+
         m_paintInfo->context->beginTransparencyLayer(opacity);
+
+        if (hasBlendMode)
+            m_paintInfo->context->setCompositeOperation(CompositeSourceOver, blink::WebBlendModeNormal);
+
         m_renderingFlags |= EndOpacityLayer;
     }
 
     ClipPathOperation* clipPathOperation = style->clipPath();
     if (clipPathOperation && clipPathOperation->type() == ClipPathOperation::SHAPE) {
         ShapeClipPathOperation* clipPath = toShapeClipPathOperation(clipPathOperation);
         m_paintInfo->context->clipPath(clipPath->path(object->objectBoundingBox()), clipPath->windRule());
     }
 
     SVGResources* resources = SVGResourcesCache::cachedResourcesForRenderObject(m_object);
@@ skipping 153 matching lines @@
             toRenderSVGImage(m_object)->paintForeground(bufferedInfo);
         } else
             return false;
     }
 
     m_paintInfo->context->drawImageBuffer(imageBuffer.get(), boundingBox);
     return true;
 }
 
 }