src/vs/platform/terminal/node/ptyHostService.ts/PtyHostService/_handleHeartbeat
class PtyHostService:	private _handleHeartbeat() {
		this._clearHeartbeatTimeouts();
		this._heartbeatFirstTimeout = setTimeout(() => this._handleHeartbeatFirstTimeout(), HeartbeatConstants.BeatInterval * HeartbeatConstants.FirstWaitMultiplier);
		if (!this._isResponsive) {
			/* __GDPR__
				"ptyHost/responsive" : {}
			*/
			this._telemetryService.publicLog('ptyHost/responsive');
			this._isResponsive = true;
		}
		this._onPtyHostResponsive.fire();
	}