Flood functions with breakpoints to prepare them for stepping. With a
small modification to the runtime function, this already implements a
basic step over functionality.

We still cannot resume, step in or step out (including stepping over a
return instruction).

R=clemensb@chromium.org

Bug: v8:10321
Change-Id: Ia4a6335d24c1a511c2f1fc9b48d728f327b3df56
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2098732Reviewed-by: Simon Zünd <szuend@chromium.org>
Reviewed-by: Clemens Backes <clemensb@chromium.org>
Commit-Queue: Thibaud Michaud <thibaudm@chromium.org>
Cr-Commit-Position: refs/heads/master@{#66697}