Omnibox: Add New Histogram Description
Omnibox: Add New Histogram Description

This synthetic histogram was added in cr/112843755

BUG=

Review URL: https://codereview.chromium.org/1652953003

Cr-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#372818}

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