Currently layerTreeAsText doesn't provide any info on how blend mode is propagated to GraphicsLayers. There are some cases we should check if blend mode is correctly set, for example, when the blending layer has an ancestor clipping layer.
Created attachment 226910 [details] path v1
Don't forget to proper guard the blending changes with #ifdef ENABLE(CSS_COMPOSITING) // blending code #endif
Created attachment 226911 [details] path v2
Comment on attachment 226911 [details] path v2 Clearing flags on attachment: 226911 Committed r165804: <http://trac.webkit.org/changeset/165804>
All reviewed patches have been landed. Closing bug.