Add gerrit dependency to your change.

gistfile1.txt

git fetch --all # Make sure we have latest info from the repository
git review -d 1234 # Gerrit change number of the change you want as dependency ("parent")
git branch # Take note of the review/* branch that was created for this, it has an "*" in front of it
git checkout bug/1234 # Check out the local topic branch of your change
git rebase review/john/7000 # The branch name of the gerrit change we checked out earlier

# Resolve conflicts if needed,

git log -n5 --decorate --pretty=oneline # Verify that the last 5 entries of the log now start with:
# * (HEAD, bug/1234) your change
# * (review/john/700) the dependency
# * (gerrit/master)

git push gerrit HEAD:refs/for/master # Use this instead of `git review`