Summary
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Make `UseOSErrorReporting` a Windows-only product flag

Problem
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`UseOSErrorReporting` is defined as a cross-platform flag but only actually works on Windows (there is an open question on whether it works even on Windows). If you turn this on for other platforms you are guaranteed to trigger a 2 minute hang.

Solution
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Make `UseOSErrorReporting` a Windows-only product flag.

Specification
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Remove the definition from globals.hpp:

    !  product_pd(bool, UseOSErrorReporting,                                     \
    !          "Let VM fatal error propagate to the OS (ie. WER on Windows)")    \

Add it to globals_windows.hpp:

    ! product(bool, UseOSErrorReporting, false,                                  \
    !        "Let VM fatal error propagate to the OS (ie. WER on Windows)")