profiler: add function to check if function name is within a particular file in the profile
profiler: add function to check if function name is within a particular file in the profile

Change-Id: Iad76c428e4df329919b664bd19ccd656a1625526
Reviewed-on: https://code-review.googlesource.com/c/36950
Reviewed-by: Jianqiao Li <2d515f767da37bdb8a87cabf23e3e650ab8dc69c@google.com>

googleapis/google-cloud-go,googleapis/google-cloud-go,googleapis/google-cloud-go,googleapis/google-cloud-go