update_scripts failing on chromium.perf/Win x64 Builder

Builders failed on: 
- Win x64 Builder: 
  https://build.chromium.org/p/chromium.perf/builders/Win%20x64%20Builder


https://uberchromegw.corp.google.com/i/chromium.perf/buildslaves/build197-m1 is failing; it probably needs a git cache wip, or clobber or something. I'll look into that today.