src/vs/platform/log/common/bufferLog.ts/BufferLogService/_log
class BufferLogService:	private _log(level: LogLevel, ...args: any[]): void {
		if (this._logger) {
			const fn = getLogFunction(this._logger, level);
			fn.apply(this._logger, args);
		} else if (this.getLevel() <= level) {
			this.buffer.push({ level, args });
		}
	}