v0.8.2: Various stability improvements/fixes:

- fixed concurrency errrors in Sample.java
- added a null safety check to IconTitle
- fixed further rare freezing errors with tengu jumping
- reverted Android 'singleInstance' change, due to stability issues

core/src/main/java/com/shatteredpixel/shatteredpixeldungeon/actors/mobs/NewTengu.java

@@ -241,13 +241,17 @@ public class NewTengu extends Mob {
 			if (level.state() == NewPrisonBossLevel.State.FIGHT_START) {
 				
 				level.cleanTenguCell();
-				
+
+				int tries = 100;
 				do {
 					newPos = ((NewPrisonBossLevel)Dungeon.level).randomTenguCellPos();
-				} while ( level.trueDistance(newPos, enemy.pos) <= 3.5f
+					tries--;
+				} while ( tries > 0 && (level.trueDistance(newPos, enemy.pos) <= 3.5f
 						|| level.trueDistance(newPos, Dungeon.hero.pos) <= 3.5f
-						|| Actor.findChar(newPos) != null);
-				
+						|| Actor.findChar(newPos) != null));
+
+				if (tries <= 0) newPos = pos;
+
 				if (level.heroFOV[pos]) CellEmitter.get( pos ).burst( Speck.factory( Speck.WOOL ), 6 );
 				
 				sprite.move( pos, newPos );

core/src/main/java/com/shatteredpixel/shatteredpixeldungeon/windows/IconTitle.java

@@ -109,8 +109,10 @@ public class IconTitle extends Component {
 	}
 
 	public void icon( Image icon ) {
-		remove( imIcon );
-		add( imIcon = icon );
+		if (icon != null) {
+			remove(imIcon);
+			add(imIcon = icon);
+		}
 	}
 
 	public void label( String label ) {