Automatic imports are not showing in some cases

[alexrock]

TypeScript Version: 2.7.0-dev.20180111

I am still having problems here.

Code

b.d.ts

declare namespace N {
	export const xxx: number
}

declare module 'n' {
	export = N
}

c.d.ts

declare namespace N.O {
	export const yyy: number
}

declare module 'n-o' {
	export = N.O
}

a.ts

xx/**/ // fail
yy/**/ // ok

Joining these definition files in just one file, everything works fine.

Related:
#20951