RFR: 8368675: IGV: nodes are wrongly marked as changed in the difference view

Fri Sep 26 09:04:44 UTC 2025

This changeset refines IGV's node difference analysis to ignore changes in node properties that are derived by IGV, as opposed to generated by HotSpot. Derived properties include the label and color of each node. Ignoring changes in these properties prevents IGV from wrongly marking equal nodes as "changed" (colored in yellow) when showing the difference between two graphs:

<img width="2323" height="651" alt="before-after" src="https://github.com/user-attachments/assets/ea51c86d-4719-45c0-b615-e6e4b8aec023" />

**Testing:** tier1 and manual testing on a few graphs.

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Commit messages:
 - Ignore 'label' and 'color' properties when analyzing node changes

Changes: https://git.openjdk.org/jdk/pull/27515/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=27515&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8368675
  Stats: 27 lines in 5 files changed: 14 ins; 2 del; 11 mod
  Patch: https://git.openjdk.org/jdk/pull/27515.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/27515/head:pull/27515

PR: https://git.openjdk.org/jdk/pull/27515