RFR: 8165943: LineBreakMeasurer does not measure correctly if TextAttribute.TRACKING is set.

[Olga Mikhaltsova]

This is a fix for LineBreakMeasurer. It takes into account the TextAttribute.TRACKING value (not eq 0) while calculating the line breaks.

Tested on Linux x64, Windows x64, macOS x64 with the reproducer (LineBreakSample.java) attached to JDK-8165943 and the following group of tests:
`$JTREG_HOME/bin/jtreg -jdk:$BUILD_HOME ./test/jdk/java/awt/font`

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Commit messages:
 - Removed unnecessary comment
 - 8165943: LineBreakMeasurer does not measure correctly if TextAttribute.TRACKING is set.

Changes: https://git.openjdk.org/jdk/pull/10289/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=10289&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8165943
  Stats: 33 lines in 2 files changed: 29 ins; 0 del; 4 mod
  Patch: https://git.openjdk.org/jdk/pull/10289.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/10289/head:pull/10289

PR: https://git.openjdk.org/jdk/pull/10289