RFR: 8243953: Optimize encoder creation/deletion logic for LCD text rendering

[Jayathirth D V]

Improve usage of encoder creation and deletion logic for LCD cached rendering so that we create only one encoder per
DrawGlyphList.

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Commit messages:
 - 8243953: Optimize encoder creation/deletion logic for LCD text rendering

Changes: https://git.openjdk.java.net/lanai/pull/61/files
 Webrev: https://webrevs.openjdk.java.net/lanai/61/webrev.00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8243953
  Stats: 98 lines in 1 file changed: 85 ins; 8 del; 5 mod
  Patch: https://git.openjdk.java.net/lanai/pull/61.diff
  Fetch: git fetch https://git.openjdk.java.net/lanai pull/61/head:pull/61

PR: https://git.openjdk.java.net/lanai/pull/61