runelite-client: remove various redundant null checks

runelite-client/src/main/java/net/runelite/client/plugins/devtools/SceneOverlay.java

@@ -252,10 +252,6 @@ public class SceneOverlay extends Overlay
 			lp = new LocalPoint(
 				lp.getX() + dx * Perspective.LOCAL_TILE_SIZE + dx * Perspective.LOCAL_TILE_SIZE * (area.getWidth() - 1) / 2,
 				lp.getY() + dy * Perspective.LOCAL_TILE_SIZE + dy * Perspective.LOCAL_TILE_SIZE * (area.getHeight() - 1) / 2);
-			if (lp == null)
-			{
-				return;
-			}
 
 			Polygon poly = Perspective.getCanvasTilePoly(client, lp);
 			if (poly == null)
@@ -313,10 +309,6 @@ public class SceneOverlay extends Overlay
 	private void renderTileIfHasLineOfSight(Graphics2D graphics, WorldArea start, int targetX, int targetY)
 	{
 		WorldPoint targetLocation = new WorldPoint(targetX, targetY, start.getPlane());
-		if (targetLocation == null)
-		{
-			return;
-		}
 
 		// Running the line of sight algorithm 100 times per frame doesn't
 		// seem to use much CPU time, however rendering 100 tiles does

runelite-client/src/main/java/net/runelite/client/plugins/instancemap/InstanceMapOverlay.java

@@ -172,11 +172,6 @@ class InstanceMapOverlay extends Overlay
 			drawPlayerDot(graphics, client.getLocalPlayer(), Color.white, Color.black);
 		}
 
-		if (image == null)
-		{
-			return null;
-		}
-
 		return new Dimension(image.getWidth(), image.getHeight());
 	}
 

runelite-client/src/main/java/net/runelite/client/plugins/kourendlibrary/KourendLibraryOverlay.java

@@ -86,11 +86,6 @@ public class KourendLibraryOverlay extends Overlay
 
 		List<Bookcase> allBookcases = library.getBookcasesOnLevel(client.getPlane());
 
-		if (allBookcases == null)
-		{
-			return null;
-		}
-
 		for (Bookcase bookcase : allBookcases)
 		{
 			// AABB

runelite-client/src/main/java/net/runelite/client/plugins/puzzlesolver/solver/pathfinding/IDAStar.java

@@ -47,11 +47,6 @@ public class IDAStar extends Pathfinder
 	{
 		PuzzleState goalNode = path(root);
 
-		if (goalNode == null)
-		{
-			return null;
-		}
-
 		List<PuzzleState> path = new ArrayList<>();
 
 		PuzzleState parent = goalNode;