This is a reland of 3dfaf826

Original change's description:
> [debug] liveedit in native
>
> Liveedit step-by-step:
> 1. calculate diff between old source and new source,
> 2. map function literals from old source to new source,
> 3. create new script for new_source,
> 4. mark literals with changed code as changed, all others as unchanged,
> 5. check that for changed literals there are no:
>   - running generators in the heap,
>   - non droppable frames (e.g. running generator) above them on stack.
> 6. mark the bottom most frame with changed function as scheduled for
>    restart if any.
> 7. for unchanged functions:
>   - deoptimize,
>   - remove from cache,
>   - update source positions,
>   - move to new script,
>   - reset feedback information and preparsed scope information if any,
>   - replace any sfi in constant pool with changed one if any.
> 8. for changed functions:
>   - deoptimize
>   - remove from cache,
>   - reset feedback information,
>   - update all links from js functions to old shared with new one.
> 9. swap scripts.
>
> TBR=ulan@chromium.org
>
> Bug: v8:7862,v8:5713
> 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: I8f6f6156318cc82d6f36d7ebc1c9f7d5f3aa1461
> Reviewed-on: https://chromium-review.googlesource.com/1105493
> Reviewed-by: Aleksey Kozyatinskiy <kozyatinskiy@chromium.org>
> Reviewed-by: Dmitry Gozman <dgozman@chromium.org>
> Reviewed-by: Yang Guo <yangguo@chromium.org>
> Commit-Queue: Aleksey Kozyatinskiy <kozyatinskiy@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#54146}

TBR=dgozman@chromium.org

Bug: v8:7862, v8:5713
Change-Id: I163ed2fd2ca3115ba0de74cb35a6fac9e40fdd94
Cq-Include-Trybots: luci.chromium.try:linux_chromium_headless_rel;luci.chromium.try:linux_chromium_rel_ng;master.tryserver.blink:linux_trusty_blink_rel
Reviewed-on: https://chromium-review.googlesource.com/1124879
Commit-Queue: Aleksey Kozyatinskiy <kozyatinskiy@chromium.org>
Reviewed-by: Aleksey Kozyatinskiy <kozyatinskiy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#54187}