[jfx17u] RFR: 8345870: Failed to compile test/javafx/scene/web/CSSRoundingTest.java after 8336798

[Sergey Chernyshev]

Hi,

this PR fixes the build failure after backporting JDK-8336798 [1].
The test CSSRoundingTest.java uses multiline string literals, that are not supported with -source 11.


[1] https://bugs.openjdk.org/browse/JDK-8336798

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Commit messages:
 - 8345870: Failed to compile test/javafx/scene/web/CSSRoundingTest.java after 8336798

Changes: https://git.openjdk.org/jfx17u/pull/221/files
  Webrev: https://webrevs.openjdk.org/?repo=jfx17u&pr=221&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8345870
  Stats: 48 lines in 1 file changed: 0 ins; 3 del; 45 mod
  Patch: https://git.openjdk.org/jfx17u/pull/221.diff
  Fetch: git fetch https://git.openjdk.org/jfx17u.git pull/221/head:pull/221

PR: https://git.openjdk.org/jfx17u/pull/221