Add Measure::as_duration()

[brooksprumo]

Problem

Measure does not have a method to return its duration as a Duration. I've found myself wanting this method to use when interfacing with other code that takes in a Duration.

Summary of Changes

Add as_duration() to Measure.

[apfitzge]

Looks good.

Though, it seems slightly strange we have a duration from elapsed and then rebuild it from the ns. But not sure there's any benefit changing the measure to store Duration instead.

[brooksprumo]

Though, it seems slightly strange we have a duration from elapsed and then rebuild it from the ns. But not sure there's any benefit changing the measure to store Duration instead.

Yep, agreed. I figured this PR didn't need to address that underlying issue. A Duration type is 12 bytes, versus 8 B with just a u64 currently. I can't imagine that this would be a big performance drain, so a future PR could likely change the duration field to an actual Duration and simplify the impl.

[mergify]

automerge label removed due to a CI failure

[codecov]

Codecov Report

Merging #25942 (68b5142) into master (8caced6) will decrease coverage by 0.1%.
The diff coverage is 77.6%.

@@            Coverage Diff            @@
##           master   #25942     +/-   ##
=========================================
- Coverage    82.1%    82.0%   -0.2%     
=========================================
  Files         628      631      +3     
  Lines      171471   172926   +1455     
=========================================
+ Hits       140878   141874    +996     
- Misses      30593    31052    +459