Rename base::ElapsedTimer::Begin() to start_time()

From the current naming, it's easy to mistakenly assume that the
function starts the time - as evidenced by >50% of existing usages
making this error.

I've updated the naming to move obviously look like a getter for the
start time.

Updated existing usages (including removing an expired histogram in
passing).

#codehealth

Change-Id: Ib212809328723a0223b772d18cbdf0ac1aa0db9b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4902498
Reviewed-by: Mustafa Emre Acer <meacer@chromium.org>
Reviewed-by: Wez <wez@chromium.org>
Reviewed-by: ccameron chromium <ccameron@chromium.org>
Auto-Submit: James Lee <ljjlee@google.com>
Commit-Queue: ccameron chromium <ccameron@chromium.org>
Reviewed-by: Alexander Bolodurin <alexbn@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1207018}


CrOS-Libchrome-Original-Commit: db0f34dd13896435a29e7a19ac1f36bc50190b48
3 files changed
tree: bec5edaa1f33f128f44adca92cf1862bdb7e4ec3
  1. base/
  2. build/
  3. components/
  4. dbus/
  5. device/
  6. ipc/
  7. mojo/
  8. testing/
  9. third_party/
  10. ui/