Revert "don't close the tree view on cmd-w"
Revert "don't close the tree view on cmd-w"

This reverts commit ef48c355fbabbb668d723dfea74a696382828d81.

matthewbauer/tree-view,tbryant/tree-view,learn-co/learn-ide-tree,jasonhinkle/tree-view,thgaskell/tree-view,ALEXGUOQ/tree-view,atom/tree-view,samu/tree-view,benjaminRomano/tree-view,tomekwi/tree-view,rajendrant/tree-view-remote,laituan245/tree-view,cgrabowski/webgl-studio-tree-view,pombredanne/tree-view-1,jarig/tree-view,Galactix/tree-view,ayumi/tree-view