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+ Add myself to the src/tracing/OWNERS

BUG=chromium:895974

Change-Id: I410a09d44af08b61837579fa09d263d897b9385e
Reviewed-on: https://chromium-review.googlesource.com/c/1303535Reviewed-by: Yang Guo <yangguo@chromium.org>
Reviewed-by: Dmitry Gozman <dgozman@chromium.org>
Commit-Queue: Alexei Filippov <alph@chromium.org>
Cr-Commit-Position: refs/heads/master@{#57180}