misc/emacs: Make godef-jump behave more like find-tag by supporting pop-tag-mark
misc/emacs: Make godef-jump behave more like find-tag by supporting pop-tag-mark

Push point to the find-tag marker ring to support pop-tag-mark.

Fixes issue 5804.

R=adonovan
CC=golang-dev
https://codereview.appspot.com/11457044

Committer: Alan Donovan <7069e9552f9d110b0a0f326b96f22f63fb99dfc1@google.com>

h8liu/golang,h8liu/golang,h8liu/golang,h8liu/golang,h8liu/golang,h8liu/golang,h8liu/golang