Integrated: 6787: Simplified stack trace tree model

[Alex Ciminian]

On Wed, 11 Nov 2020 17:52:23 GMT, Alex Ciminian <github.com+348973+cimi at openjdk.org> wrote:

> This PR adds a new way to represent JFR data - we aggregate stacktraces into a tree structure which we then allow to be serialised to JSON so we can use it in the `FlameGraphView`.
> 
> The `Node` and `AggregatableFrame` classes were initially copied from the new graph representation then slightly modified. Once the two implementations are merged and stabilised we should consider unifying these models.
> 
> We've validated the output of the new JSON serialisation against the previous flame graph JSON implementation, before removing the legacy code. The intermediary commits have tests that check the output is identical for one of our test recording, using the various configuration options (with/without a target attribute, with thread root at top/bottom).

This pull request has now been integrated.

Changeset: 00d14cd3
Author:    Alex Ciminian <alexandru.ciminian at datadoghq.com>
Committer: Guru Hb <ghb at openjdk.org>
URL:       https://git.openjdk.java.net/jmc/commit/00d14cd3
Stats:     1391 lines in 24 files changed: 939 ins; 441 del; 11 mod

6787: Simplified stack trace tree model

Reviewed-by: hirt, ghb

-------------

PR: https://git.openjdk.java.net/jmc/pull/159