RFR: 8191758: Match WebKit's font weight rendering with JavaFX

[Bhawesh Choudhary]

As per JavaFx 700 font weight is considered to be bold but webkit is using 600 font weight for text to become bold. to
fix issue, use boldWeightValue() function which uses 700 font weight rather than isFontWeightBold() which compare
against 600 font weight.

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Commit messages:
 - 8191758: Match WebKit's font weight rendering with JavaFX

Changes: https://git.openjdk.java.net/jfx/pull/180/files
 Webrev: https://webrevs.openjdk.java.net/jfx/180/webrev.00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8191758
  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.java.net/jfx/pull/180.diff
  Fetch: git fetch https://git.openjdk.java.net/jfx pull/180/head:pull/180

PR: https://git.openjdk.java.net/jfx/pull/180