src/vs/workbench/api/common/extHostLanguageFeatures.ts/CallHierarchyAdapter/_cacheAndConvertItem
class CallHierarchyAdapter:	private _cacheAndConvertItem(sessionId: string, item: vscode.CallHierarchyItem): extHostProtocol.ICallHierarchyItemDto {
		const map = this._cache.get(sessionId)!;
		const dto: extHostProtocol.ICallHierarchyItemDto = {
			_sessionId: sessionId,
			_itemId: map.size.toString(36),
			name: item.name,
			detail: item.detail,
			kind: typeConvert.SymbolKind.from(item.kind),
			uri: item.uri,
			range: typeConvert.Range.from(item.range),
			selectionRange: typeConvert.Range.from(item.selectionRange),
			tags: item.tags?.map(typeConvert.SymbolTag.from)
		};
		map.set(dto._itemId, item);
		return dto;
	}