This changes the behavior of SetBreakpointForScript to find more
accurate break positions.

Previously, setting a breakpoint would only consider the shared
function info that contained the requested position for setting a
breakpoint. More intuitively, a breakpoint should not necessarily
be set in a function that contains the position, but in the closest
breakable location that comes after the position we requested.

To achieve this we:
1. find the shared function info of the inner most function
that contains the requested_position.
This function's end position is used to find other shared function
infos in step 2.

2. search for all shared function infos that intersect with the
range [requested_position, inner_most_function.break_position[.

3. From the shared function infos extracted in 2, find the one
that has the closest breakable location to requested_position.

Also-By: bmeurer@chromium.org
Fixed: chromium:1137141
Change-Id: I4f4c6c3aac1ebea50cbcad9543b539ab1ded2b05
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2742198
Commit-Queue: Kim-Anh Tran <kimanh@chromium.org>
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#73392}

- rewritten couple tests,
- migrated JSMessageObject to real Script instead of wrapper,
- removed wrapper.

R=yangguo@chromium.org
TBR=ulan@chromium.org

Bug: v8:5530
Cq-Include-Trybots: luci.chromium.try:linux_chromium_headless_rel;luci.chromium.try:linux_chromium_rel_ng;master.tryserver.blink:linux_trusty_blink_rel
Change-Id: Ia95492344c7b5978a940e2ab007b389384537148
Reviewed-on: https://chromium-review.googlesource.com/1112851Reviewed-by: Aleksey Kozyatinskiy <kozyatinskiy@chromium.org>
Reviewed-by: Yang Guo <yangguo@chromium.org>
Commit-Queue: Aleksey Kozyatinskiy <kozyatinskiy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#54274}