RFR: 8370235: WebKit build fails on Windows 32-bit and Linux 32-bit after JDK-8367578

[Jay Bhaskar]

Issue: WebKit build fails on Windows 32-bit and Linux 32-bit after JDK-8367578
Solution: [JSC] Use llintOpWithReturn for instanceof on 32-bits
https://github.com/WebKit/WebKit/commit/05f6e3818e1be6d1186ebfd5e059f669361edf0a

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Commit messages:
 - 8370235: WebKit build fails on Windows 32-bit and Linux 32-bit after JDK-8367578

Changes: https://git.openjdk.org/jfx/pull/1952/files
  Webrev: https://webrevs.openjdk.org/?repo=jfx&pr=1952&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8370235
  Stats: 9 lines in 1 file changed: 8 ins; 1 del; 0 mod
  Patch: https://git.openjdk.org/jfx/pull/1952.diff
  Fetch: git fetch https://git.openjdk.org/jfx.git pull/1952/head:pull/1952

PR: https://git.openjdk.org/jfx/pull/1952