RFR: 8262276: Debug build of WebKit fails [v3]

[Arun Joseph]

> Fixing the Debug build of WebKit.
> 
> Test: Build JavaFX using `-PCOMPILE_WEBKIT=true -PCONF=DebugNative` and test using a simple HelloWebView app.

Arun Joseph has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains three commits:

 - Merge
 - Fix InternalFunction crash
 - 8262276: Debug build of WebKit fails

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Changes: https://git.openjdk.java.net/jfx/pull/417/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jfx&pr=417&range=02
  Stats: 34 lines in 6 files changed: 21 ins; 0 del; 13 mod
  Patch: https://git.openjdk.java.net/jfx/pull/417.diff
  Fetch: git fetch https://git.openjdk.java.net/jfx pull/417/head:pull/417

PR: https://git.openjdk.java.net/jfx/pull/417