Reland of Sampling heap profiler data structure changes (patchset #1 id:1 of https://codereview.chromium.org/1708363002/ )

Reason for revert:
Failure keeps lurking around after the revert. I'll reland, sorry for the inconvenience!

Original issue's description:
> Revert of Sampling heap profiler data structure changes (patchset #10 id:180001 of https://codereview.chromium.org/1697903002/ )
>
> Reason for revert:
> [Sheriff] Speculative revert for cpu profiler crashes on chromebooks:
> https://build.chromium.org/p/client.v8/builders/V8%20Arm%20-%20debug/builds/549
> https://build.chromium.org/p/client.v8/builders/V8%20Arm%20-%20debug/builds/550
>
> Original issue's description:
> > Sampling heap profiler data structure changes
> >
> > Previously, the sampling heap profiler stored a list of samples and then
> > built a tree representation when the profile was queried by calling
> > GetAllocationProfile. This change reduces duplication by removing stacks
> > from all samples. Also, less information is stored in the tree
> > maintained by the profiler and remaining information (script name, line
> > no, etc) is resolved when a profile is requested.
> >
> > BUG=
> >
> > Committed: https://crrev.com/cdd55e2a3717723492d76f66810bf56b8de7f198
> > Cr-Commit-Position: refs/heads/master@{#34119}
>
> TBR=ofrobots@google.com,ulan@chromium.org,hpayer@chromium.org,mattloring@google.com
> # Skipping CQ checks because original CL landed less than 1 days ago.
> NOPRESUBMIT=true
> NOTREECHECKS=true
> NOTRY=true
> BUG=
>
> Committed: https://crrev.com/4578e52aefb8c4727742ce2e254613e482fdad1f
> Cr-Commit-Position: refs/heads/master@{#34128}

TBR=ofrobots@google.com,ulan@chromium.org,hpayer@chromium.org,mattloring@google.com
# Skipping CQ checks because original CL landed less than 1 days ago.

Review URL: https://codereview.chromium.org/1714493003

Cr-Commit-Position: refs/heads/master@{#34140}