RFR: 7175396: The text on label is not painted red for Nimbus LaF.

[Prasanta Sadhukhan]

Label.foreground UIProperty is not honored by Nimbus L&F. It needs to be Label[Enabled].textForeground which is the corresponding Synth property
Added support for setting JLabel foreground color for Nimbus L&F

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

Commit messages:
 - 7175396: The text on label is not painted red for Nimbus LaF.
 - 7175396: The text on label is not painted red for Nimbus LaF.

Changes: https://git.openjdk.org/jdk/pull/11660/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=11660&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-7175396
  Stats: 146 lines in 2 files changed: 145 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/11660.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/11660/head:pull/11660

PR: https://git.openjdk.org/jdk/pull/11660