If Symbols are supported then get the property of the global Symbol, if Symbol's are
not supported and noPoly is true it returns null. Used to access the well known symbols.
// If Symbol is supported in the runtime getKnownSymbol("toStringTag") === Symbol.toStringTag; // true getKnownSymbol(WellKnownSymbols.toStringTag) === Symbol.toStringTag; // true
If Symbols are supported then get the property of the global Symbol, if Symbol's are not supported and noPoly is true it returns null. Used to access the well known symbols.