Merge "Fix setPositionListener race condition" into qt-dev

}

void RenderNode::pushStagingPropertiesChanges(TreeInfo& info) {

    if (mPositionListenerDirty) {

        mPositionListener = std::move(mStagingPositionListener);

        mStagingPositionListener = nullptr;

        mPositionListenerDirty = false;

    }

    // Push the animators first so that setupStartValueIfNecessary() is called

    // before properties() is trampled by stagingProperties(), as they are

    // required by some animators.

        virtual void onPositionLost(RenderNode& node, const TreeInfo* info) = 0;

    };

    // Note this is not thread safe, this needs to be called

    // before the RenderNode is used for drawing.

    // RenderNode takes ownership of the pointer

    ANDROID_API void setPositionListener(PositionListener* listener) {

        mPositionListener = listener;

        mStagingPositionListener = listener;

        mPositionListenerDirty = true;

    }

    // This is only modified in MODE_FULL, so it can be safely accessed

    // mDisplayList, not mStagingDisplayList.

    uint32_t mParentCount;

    bool mPositionListenerDirty = false;

    sp<PositionListener> mStagingPositionListener;

    sp<PositionListener> mPositionListener;

    UsageHint mUsageHint = UsageHint::Unknown;