Update telemetry tests to be agnostic to ScrollTopLeftInterop mode

See https://dev.opera.com/articles/fixing-the-scrolltop-bug/
for details of the issue.  It should be possible to run telemetry
with --enable-experimental-web-platform-features.

BUG=157855
CQ_EXTRA_TRYBOTS=tryserver.chromium.perf:linux_perf_bisect;tryserver.chromium.perf:mac_10_10_perf_bisect;tryserver.chromium.perf:win_perf_bisect;tryserver.chromium.perf:android_nexus5_perf_bisect

Review URL: https://codereview.chromium.org/1428733002

Cr-Commit-Position: refs/heads/master@{#356947}
5 files changed