8141132: JEP 254: Compact Strings

Adopt a more space-efficient internal representation for strings.

Co-authored-by: Brent Christian <brent.christian@oracle.com>
Co-authored-by: Vivek Deshpande <vivek.r.deshpande@intel.com>
Co-authored-by: Charlie Hunt <charlie.hunt@oracle.com>
Co-authored-by: Vladimir Kozlov <vladimir.kozlov@oracle.com>
Co-authored-by: Roger Riggs <roger.riggs@oracle.com>
Co-authored-by: Xueming Shen <xueming.shen@oracle.com>
Co-authored-by: Aleksey Shipilev <aleksey.shipilev@oracle.com>
Co-authored-by: Sandhya Viswanathan <sandhya.viswanathan@intel.com>
Reviewed-by: alanb, bdelsart, coleenp, iklam, jiangli, jrose, kevinw, naoto, pliden, roland, smarks, twisti
76 files changed