RFR: 8240218: IOS Webkit implementation broken

[Johan Vos]

Make modifications to javafx.web files for iOS, so that it can compile again.

Fix for JDK-8240218

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Commits:
 - 1b18d0b1: Make modifications to javafx.web files for iOS, so that it can compile again.

Changes: https://git.openjdk.java.net/jfx/pull/128/files
 Webrev: https://webrevs.openjdk.java.net/jfx/128/webrev.00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8240218
  Stats: 259 lines in 6 files changed: 224 ins; 8 del; 27 mod
  Patch: https://git.openjdk.java.net/jfx/pull/128.diff
  Fetch: git fetch https://git.openjdk.java.net/jfx pull/128/head:pull/128

PR: https://git.openjdk.java.net/jfx/pull/128