JS Backend fails deadlock test Chan002

Caught by !9552 (closed). This test used to pass and now fails:

=====> 9100 of 9257 [0, 2, 0]
Timeout happened...killed process "cd "/builds/ghc/ghc/tmp/ghctest-z05btgvd/test   spaces/testsuite/tests/typecheck/should_fail/TcCoercibleFail.run" &&  "/builds/ghc/ghc/_build/stage1/bin/js-unknown-ghcjs-ghc" -c TcCoercibleFail.hs -dcore-lint -dstg-lint -dcmm-lint -no-user-package-db -fno-dump-with-ways -rtsopts -fno-warn-missed-specialisations -fshow-warning-groups -fdiagnostics-color=never -fno-diagnostics-show-caret -Werror=compat -dno-debug-output  "...
Wrong exit code for Chan002(normal)(expected 0 , actual 1 )
Stdout ( Chan002 ):
..........................................................
Stderr ( Chan002 ):
Chan002: <stdout>: hPutStr: illegal operation (handle is finalized)
*** unexpected failure for Chan002(normal)

Marking as broken for !9552 (closed) and setting to high priority because the test used to pass.