TT: make sure it gives return

Author: kodewdle

ElvUI/Game/Shared/Modules/Tooltip/Tooltip.lua

@@ -658,7 +658,7 @@ function TT:GameTooltipStatusBar_UpdateUnitHealth(bar)
 	local tt = bar:GetParent()
 	local unit = TT:GetUnitToken(tt)
 	local ok, perc = pcall(UnitHealthPercent, unit, true, ScaleTo100)
-	if ok then
+	if ok and perc then
 		bar.Text:SetFormattedText('%d', perc)
 	else
 		bar.Text:SetText('')