src/vs/base/common/keybindings.ts/ScanCodeBinding/isDuplicateModifierCase
class ScanCodeBinding:	public isDuplicateModifierCase(): boolean {
		return (
			(this.ctrlKey && (this.scanCode === ScanCode.ControlLeft || this.scanCode === ScanCode.ControlRight))
			|| (this.shiftKey && (this.scanCode === ScanCode.ShiftLeft || this.scanCode === ScanCode.ShiftRight))
			|| (this.altKey && (this.scanCode === ScanCode.AltLeft || this.scanCode === ScanCode.AltRight))
			|| (this.metaKey && (this.scanCode === ScanCode.MetaLeft || this.scanCode === ScanCode.MetaRight))
		);
	}