src/vs/editor/common/config/editorOptions.ts/EditorScrollbar/validate
class EditorScrollbar:	public validate(_input: any): InternalEditorScrollbarOptions {
		if (!_input || typeof _input !== 'object') {
			return this.defaultValue;
		}
		const input = _input as IEditorScrollbarOptions;
		const horizontalScrollbarSize = EditorIntOption.clampedInt(input.horizontalScrollbarSize, this.defaultValue.horizontalScrollbarSize, 0, 1000);
		const verticalScrollbarSize = EditorIntOption.clampedInt(input.verticalScrollbarSize, this.defaultValue.verticalScrollbarSize, 0, 1000);
		return {
			arrowSize: EditorIntOption.clampedInt(input.arrowSize, this.defaultValue.arrowSize, 0, 1000),
			vertical: _scrollbarVisibilityFromString(input.vertical, this.defaultValue.vertical),
			horizontal: _scrollbarVisibilityFromString(input.horizontal, this.defaultValue.horizontal),
			useShadows: boolean(input.useShadows, this.defaultValue.useShadows),
			verticalHasArrows: boolean(input.verticalHasArrows, this.defaultValue.verticalHasArrows),
			horizontalHasArrows: boolean(input.horizontalHasArrows, this.defaultValue.horizontalHasArrows),
			handleMouseWheel: boolean(input.handleMouseWheel, this.defaultValue.handleMouseWheel),
			alwaysConsumeMouseWheel: boolean(input.alwaysConsumeMouseWheel, this.defaultValue.alwaysConsumeMouseWheel),
			horizontalScrollbarSize: horizontalScrollbarSize,
			horizontalSliderSize: EditorIntOption.clampedInt(input.horizontalSliderSize, horizontalScrollbarSize, 0, 1000),
			verticalScrollbarSize: verticalScrollbarSize,
			verticalSliderSize: EditorIntOption.clampedInt(input.verticalSliderSize, verticalScrollbarSize, 0, 1000),
			scrollByPage: boolean(input.scrollByPage, this.defaultValue.scrollByPage),
		};
	}