[jfx17u] RFR: 8291625: DialogPane without header nor headerText nor graphic node adds padding to the left of the content pane

[Johan Vos]

clean backport of 8291625: DialogPane without header nor headerText nor graphic node adds padding to the left of the content pane

Reviewed-by: aghaisas

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Commit messages:
 - 8291625: DialogPane without header nor headerText nor graphic node adds padding to the left of the content pane

Changes: https://git.openjdk.org/jfx17u/pull/84/files
 Webrev: https://webrevs.openjdk.org/?repo=jfx17u&pr=84&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8291625
  Stats: 47 lines in 2 files changed: 40 ins; 3 del; 4 mod
  Patch: https://git.openjdk.org/jfx17u/pull/84.diff
  Fetch: git fetch https://git.openjdk.org/jfx17u pull/84/head:pull/84

PR: https://git.openjdk.org/jfx17u/pull/84