Mechanical rename of tracing includes for /content [1/3]

This is just a mechanical rename of tracing includes.
See crrev.com/837303004 and the related bug for motivations.

BUG=451032
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Review URL: https://codereview.chromium.org/866803003

Cr-Commit-Position: refs/heads/master@{#313421}
52 files changed