Makes html_viewer apptests use osmesa
Makes html_viewer apptests use osmesa

Osmesa makes the tests run closer to a real gl environment.

BUG=none
TEST=none
R=fsamuel@chromium.org, msw@chromium.org

Review URL: https://codereview.chromium.org/1284343007

Cr-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#344106}

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