cbuildbot: run UploadSymbols for debug/trybots

At the moment, the only time UploadSymbols runs is on actual canaries.
We have it disabled for every other situation.  This means we do not
get the kind of testing we really need.

For remote trybots, still run this code, but limit ourselves to one
symbol to the staging server.  We've talked to the crash team and they
are OK with this as the load will be small.

BUG=chromium:209442
BUG=chromium:213204
TEST=`./buildbot/run_tests` passes

Change-Id: I7b67dd4b06f113f9dc4b315289134233491ccf1c
Reviewed-on: https://gerrit.chromium.org/gerrit/58626
Reviewed-by: David James <davidjames@chromium.org>
Commit-Queue: Mike Frysinger <vapier@chromium.org>
Tested-by: Mike Frysinger <vapier@chromium.org>
4 files changed