The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/ab1da09492fa8e84ae6d90151bd718efdf97d3f4

commit ab1da09492fa8e84ae6d90151bd718efdf97d3f4
Author: lawrencewu <lawrencewu@chromium.org>
Date: Fri Oct 28 18:05:54 2016

Use pickle for field trial entries in shared memory

This CL changes the data format we use to store field trials in shared
memory from custom offsets to a pickled structure, which has several
advantages. Namely, it handles offsets for us and requires less code.
We will also probably end up using this for experiment parameters as
well.

BUG= 660128 

Review-Url: https://codereview.chromium.org/2449783007
Cr-Commit-Position: refs/heads/master@{#428423}

[modify] https://crrev.com/ab1da09492fa8e84ae6d90151bd718efdf97d3f4/base/metrics/field_trial.cc