RFR: 8279794: Fix typos in BasicScrollBarUI: Laysouts a vertical scroll bar

[Alexey Ivanov]

Fixed the typo in the layout methods: “Laysouts a…” → “Lays out a…”.

The doc for `layoutHScrollbar` incorrectly referred to _vertical_ scroll bar rather than horizontal one.


I also expanded the wildcard imports.

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Commit messages:
 - 8279794: Fix typos in BasicScrollBarUI: Laysouts a vertical scroll bar

Changes: https://git.openjdk.java.net/jdk/pull/7032/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=7032&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8279794
  Stats: 49 lines in 1 file changed: 37 ins; 9 del; 3 mod
  Patch: https://git.openjdk.java.net/jdk/pull/7032.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/7032/head:pull/7032

PR: https://git.openjdk.java.net/jdk/pull/7032