Merge "Skip a step when blurring" into tm-dev am: 6d3d7bd4

            // save a snapshot of the activeSurface to use as input to the blur shaders

            blurInput = activeSurface->makeImageSnapshot();

            // TODO we could skip this step if we know the blur will cover the entire image

            //  blit the offscreen framebuffer into the destination AHB

            // blit the offscreen framebuffer into the destination AHB, but only

            // if there are blur regions. backgroundBlurRadius blurs the entire

            // image below, so it can skip this step.

            if (layer.blurRegions.size()) {

                SkPaint paint;

                paint.setBlendMode(SkBlendMode::kSrc);

                if (CC_UNLIKELY(mCapture->isCaptureRunning())) {

                } else {

                    activeSurface->draw(dstCanvas, 0, 0, SkSamplingOptions(), &paint);

                }

            }

            // assign dstCanvas to canvas and ensure that the canvas state is up to date

            canvas = dstCanvas;