RFR: 8335548: testCookieEnabled fails with WebKit 619.1

[Jay Bhaskar]

Issue : CookieEnable method returns false when WebView url is empty
Solution: Use a dummy file URI in WebView before testing cookie.

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Commit messages:
 - 8335548: testCookieEnabled fails with WebKit 619.1

Changes: https://git.openjdk.org/jfx/pull/1513/files
  Webrev: https://webrevs.openjdk.org/?repo=jfx&pr=1513&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8335548
  Stats: 17 lines in 2 files changed: 15 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/jfx/pull/1513.diff
  Fetch: git fetch https://git.openjdk.org/jfx.git pull/1513/head:pull/1513

PR: https://git.openjdk.org/jfx/pull/1513