This changes the Walk/Inspect API inside the promql package to bubble
up errors. This is done by having the inspector return an error (instead
of a bool) and then bubbling that up in the Walk. This way if any error
is encountered in the Walk() the walk will stop and return the error.
This avoids issues where errors from the Querier where being ignored
(causing incorrect promql evaluation).
Signed-off-by: Thomas Jackson <jacksontj.89@gmail.com>
Fixes#4136
404abe0f1c