src: nw2: cleanup system menu and context menu
src: nw2: cleanup system menu and context menu

https://github.com/nwjs/chromium.src/commit/a3a2acad10be76a78ce291f2714ba2e97ee69ce6

nwjs/nw.js,nwjs/nw.js,nwjs/nw.js,nwjs/nw.js,nwjs/nw.js,nwjs/nw.js