Previously we ran baseline (e.g. ignition) and one random secondary
comparison configuration (e.g. turbofan) from the list of experiments.
But Clusterfuzz imposes limitations on the total amount of fuzz tests.
Therefore this change enables more throughput by always running the
default configuration (ignition_turbofan like V8 is shipped)
additionally to the baseline and the secondary configuration.

This, hence, doubles the number of comparisons we run, with less than
50% additional runtime, since the slow baseline configuration is only
run once.

The experiments table is updated accordingly. Explicit entries running
ignition_turbofan are removed (as it always runs now), instead some
of the other configurations are increased in their relative
percentage. We also get a few new configurations that didn't run
before (e.g. forcing the slow path on x86).

No-Try: true
Bug: chromium:1100114
Change-Id: I69b2a41d78c06e556b309743a2aace1053c22f91
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2270307Reviewed-by: Liviu Rau <liviurau@chromium.org>
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#68607}