8210387: C2 compilation fails with "assert(node->_last_del == _last) failed: must have deleted the edge just produced" Summary: Refresh iterator and start from the beginning while there is progress when removing dead regions. Reviewed-by: kvn

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nbproject/private/
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test/nashorn/script/external
test/nashorn/lib
NashornProfile.txt
**/JTreport/**
**/JTwork/**