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This checks the version of the client and impl code, and throws an
exception if they are not the same.

Change-Id: I64b0d3a47a88d8490ac5fb1c174ad6fe4d9204a8
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1829915Reviewed-by: John Abd-El-Malek <jam@chromium.org>
Commit-Queue: Clark DuVall <cduvall@chromium.org>
Cr-Commit-Position: refs/heads/master@{#702520}