Instead of just showing the immediate parent(s) and immediate first
child of the current revision, display the entire topic lineage back
to the merge base with the branch, and all changes that build on this
change. Display in a scroll pane to the right of the commit info.
This makes navigation within a topic much easier, at a glance the
reviewer can see where this change fits in and what changes come
before and after it in the history.
I am not sure about the result structure returned by /related. It is
sufficient for this use case but may be too verbose and subject to
changes as this feature is iterated on in the web UI. Documentation
for /related is omitted until the project has settled on and can
commit to an output format.
Change-Id: I9b9e63a02af1c762fcad32cfef541af0b1fa9114
0cf04a7f65