Move item length checks to onUpdateRequest to do the least amount of model filtering necessary.
Move item length checks to onUpdateRequest to do the least amount of model filtering necessary.

charnpreetsingh185/jupyterlab,TypeFox/jupyterlab,eskirk/jupyterlab,jupyter/jupyterlab,TypeFox/jupyterlab,charnpreetsingh185/jupyterlab,eskirk/jupyterlab,charnpreetsingh185/jupyterlab,charnpreetsingh185/jupyterlab,TypeFox/jupyterlab,jupyter/jupyterlab,eskirk/jupyterlab,jupyter/jupyterlab,TypeFox/jupyterlab,eskirk/jupyterlab,charnpreetsingh185/jupyterlab,eskirk/jupyterlab,jupyter/jupyterlab,jupyter/jupyterlab,TypeFox/jupyterlab