7116081: USE_PRECOMPILED_HEADER=0 triggers a single threaded build of the JVM
Summary: Changed the conditional to see if the precompiled header has been specified. Also, removed the unused PrecompiledOption.
Reviewed-by: dholmes, brutisso
^build/
^dist/
/nbproject/private/
^make/netbeans/.*/build/
^make/netbeans/.*/dist/
^.hgtip