8215644: Clean up globalDefinitions_<compiler>.hpp
Summary: Remove non-existent classes from forward declarations, delete unused functions, etc.
Reviewed-by: coleenp, kbarrett
/build/
/dist/
/.idea/
nbproject/private/
/webrev
/.src-rev
/.jib/
.DS_Store
.metadata/
.recommenders/
test/nashorn/script/external
test/nashorn/lib
NashornProfile.txt
**/JTreport/**
**/JTwork/**