search: simplify computing presence of time filter
Created by: rvantonder
Stacked on https://github.com/sourcegraph/sourcegraph/pull/32707.
I want to get rid of the Fields()
method. If the dict lookup matters here we can implement a more efficient way to check whether a value exists than b.Exists(...)
but the perf hit here is negligible. Fields()
is a very gross method right now on query, because it uses the gross Values* method I added long ago to preserve value compatibility.
Test plan
Semantics-preserving.