Fix duplicate request responses.

Reapply commits d3b4bca744bc568a804f3684221d2f0f09eb8833 and
9db99440657ed7fa7715a1cf31fce7b2d694b01a that fixed that previously.
It's CAF regression time again...

Change-Id: I594ebaa01cfd584bf86a804d979d407d283c6c3d