Use strings for keys in the histogram map.

Using the MD5 hash of the name for the key makes for an
efficient mapping but calculating that hash is expensive.

A simple string-compare that first checks the length
cuts over 40% off the run-time according to the timing
tests. And since timing tests are skewed towards names
of only a few distinct lengths, the real-world
improvement should be even more.

BUG=601572

Review URL: https://codereview.chromium.org/1866423002

Cr-Commit-Position: refs/heads/master@{#385893}


CrOS-Libchrome-Original-Commit: fca9ef5451d1dc700bbf2370e1147b05ad704cfc
2 files changed
tree: 9eb6c5d044a7dfd8b86d17666cd91acacfa74dc7
  1. base/
  2. build/
  3. components/
  4. dbus/
  5. device/
  6. ipc/
  7. mojo/
  8. testing/
  9. third_party/
  10. ui/