This is a reland of f6965281

Updated the test:
1. Set profiling interval to 100us to get 10x the samples
2. Guarantee we spend at least 1ms per iteration, instead of only
bailing out if we spend more than 1ms. This gives us enough samples on
release mode.
3. Increase the time spent profiling optimized code by 50% to make sure
we have a big enough difference.

With 1000 iterations I didn't see any flakes locally so this looks solid
now.

Original change's description:
> [cpu-profiler] Log OSR code when starting the profiler
>
> OSR code doesn't hang off any JSFunction or SFI, so we missed it when
> starting up the profiler. This meant we didn't properly attribute
> ticks to SFI code. The ticks ended up going to the caller instead.
>
> There is a weak cache of OSR code per native context, so iterate that
> on profiler startup and log all the code objects.
>
> Change-Id: I2e9738b86a488b37f36ac89803561607dc76f745
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2414216
> Commit-Queue: Peter Marshall <petermarshall@chromium.org>
> Reviewed-by: Dominik Inführ <dinfuehr@chromium.org>
> Reviewed-by: Mythri Alle <mythria@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#69964}

Change-Id: Ib506e88b546008e462967259763bbf985b74b462
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2418092
Commit-Queue: Peter Marshall <petermarshall@chromium.org>
Reviewed-by: Dominik Inführ <dinfuehr@chromium.org>
Reviewed-by: Mythri Alle <mythria@chromium.org>
Cr-Commit-Position: refs/heads/master@{#69990}