invisible troll revives and can appear visible

Play a character without see invisible. Wear speed boots. Generate a troll.
Zap it with a wand of make invisible. Kill it. Stand on the same square and
wait for it to rise from the dead. It will appear as a 'T'. Hitting it then
produces the normal "Wait, there's something here you can't see!"
[ incorporate slashem-Bugs-951439 fix ]

doc/fixes35.0

@@ -70,6 +70,7 @@ a slow-moving monster hidden under a rotting corpse was not immediately
 mimic that ends up on the rogue level should not mimic a closed door
 polymorphed or shapechanged monster sometimes got erroneous hit points
 mimic should not mimic a boulder while on a pit or hole location
+reviving invisible troll could appear visible until it moves
 
 
 Platform- and/or Interface-Specific Fixes

src/zap.c

@@ -517,6 +517,7 @@ coord *cc;
 		mtmp2->mstun = 0;
 		mtmp2->mconf = 0;
 		replmon(mtmp,mtmp2);
+		newsym(mtmp2->mx, mtmp2->my);	/* Might now be invisible */
 
 		/* in case Protection_from_shape_changers is different
 		   now than it was when the traits were stored */