npm ERR! enoent ENOENT: no such file or directory, rename

[flatmax]

When @polymer/font-roboto is nested inside other element's node_modules npm will fail to install reporting :
npm ERR! path element/node_modules/.staging/@polymer/font-roboto-22e51083
npm ERR! code ENOENT
npm ERR! errno -2
npm ERR! syscall rename
npm ERR! enoent ENOENT: no such file or directory, rename 'element/node_modules/.staging/@polymer/font-roboto-22e51083' -> 'element2/node_modules/@polymer/font-roboto'

npm i doesn't install correctly and fails to install. The nesting is like so :
element2/node_modules/element/node_modules/@polymer/font-roboto
The conflict is around :
element2/node_modules/@polymer/font-roboto

The current fix is the same as for other nesting issues :
Polymer/polymer#5407

Not very elegant, but it works.