RFR: 8368775: Remove outdated comment in OutlineTextRenderer

[Phil Race]

On Fri, 26 Sep 2025 11:23:03 GMT, Daniel Gredler <dgredler at openjdk.org> wrote:

> Until [JDK-4138921](https://bugs.openjdk.org/browse/JDK-4138921), `TextLayout` did not accept empty strings in the constructor. This limitation has been removed. However, there is a guard condition in `OutlineTextRenderer` which checks for an empty string before trying to use `TextLayout` which explicitly calls out this limitation in a code comment. We should remove the out-of-date comment but leave the check in as an optimization (see discussion in PR #26947).

Marked as reviewed by prr (Reviewer).

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PR Review: https://git.openjdk.org/jdk/pull/27523#pullrequestreview-3273510055