ensureTooltipVisible method
Shows the tooltip if it is not already visible.
After made visible by this method, the tooltip does not automatically dismiss after RawTooltip.hoverDelay until the user dismisses/re-triggers it, or RawTooltip.dismissAllToolTips is called.
Returns false when the tooltip shouldn't be shown or when the tooltip
was already visible.
Implementation
bool ensureTooltipVisible() {
return _tooltipKey.currentState?.ensureTooltipVisible() ?? false;
}