Merge "surfaceflinger: fix fencing when composition mode switches" am: 42ddbb44

        displayDevice->onSwapBuffersCompleted();

        displayDevice->makeCurrent(mEGLDisplay, mEGLContext);

        for (auto& layer : displayDevice->getVisibleLayersSortedByZ()) {

            sp<Fence> releaseFence = Fence::NO_FENCE;

            if (layer->getCompositionType(hwcId) == HWC2::Composition::Client) {

                releaseFence = displayDevice->getClientTargetAcquireFence();

            } else {

            // The layer buffer from the previous frame (if any) is released

            // by HWC only when the release fence from this frame (if any) is

            // signaled.  Always get the release fence from HWC first.

            auto hwcLayer = layer->getHwcLayer(hwcId);

                releaseFence = mHwc->getLayerReleaseFence(hwcId, hwcLayer);

            sp<Fence> releaseFence = mHwc->getLayerReleaseFence(hwcId, hwcLayer);

            // If the layer was client composited in the previous frame, we

            // need to merge with the previous client target acquire fence.

            // Since we do not track that, always merge with the current

            // client target acquire fence when it is available, even though

            // this is suboptimal.

            if (layer->getCompositionType(hwcId) == HWC2::Composition::Client) {

                releaseFence = Fence::merge("LayerRelease", releaseFence,

                        displayDevice->getClientTargetAcquireFence());

            }

            layer->onLayerDisplayed(releaseFence);

        }

        if (hwcId >= 0) {