message: Added the default 'mesh' and appropriate tooltip in gateway section of VirtualService overview, when no gateway is set.
diff: @@ -115,6 +115,32 @@ class VirtualServiceOverview extends React.Component<VirtualServiceProps> {
  );
  }
  + generateEmptyGateways() {
  + return (
  + <>
  + <Text component={TextVariants.h3}>Gateways</Text>
  + <ul className={'details'}>
  + <li key={'gateway_mesh'}>
  + <div>
  + mesh
  + <Tooltip
  + position={TooltipPosition.right}
  + content={
  + <div style={{ textAlign: 'left' }}>
  + When this field is omitted, the default gateway (mesh) will be used, which would apply the rule to
  + all sidecars in the mesh
  + </div>
  + }
  + >
  + <KialiIcon.Info className={infoStyle} />
  + </Tooltip>
  + </div>
  + </li>
  + </ul>
  + </>
  + );
  + }
  +
  generateServiceList(routes: HTTPRoute[] | TLSRoute[] | TCPRoute[], isValid: boolean) {
  const hosts: string[] = [];
  routes.forEach(route => {
  @@ -156,6 +182,9 @@ class VirtualServiceOverview extends React.Component<VirtualServiceProps> {
  {virtualService.spec.gateways && virtualService.spec.gateways.length > 0 && (
  <StackItem id={'gateways'}>{this.generateGatewaysList(virtualService.spec.gateways, isValid)}</StackItem>
  )}
  + {(!virtualService.spec.gateways || virtualService.spec.gateways.length === 0) && (
  + <StackItem id={'gateways'}>{this.generateEmptyGateways()}</StackItem>
  + )}
  {protocols.map((protocol, i) => {
  const { name, object } = protocol;
  if (object && object.length > 0) {
  