8218628: Add detailed message to NullPointerException describing what is null.
Summary: This is the implementation of JEP 358: Helpful NullPointerExceptions.
Reviewed-by: coleenp, clanger, rschmelter, rriggs, forax, mr
Manifest-Version: 1.0
OpenIDE-Module: com.sun.hotspot.igv.layout
OpenIDE-Module-Localizing-Bundle: com/sun/hotspot/igv/layout/Bundle.properties
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