deob: Make NonloadingClassWriter better at not loading classes

deobfuscator/src/main/java/net/runelite/asm/objectwebasm/NonloadingClassWriter.java

@@ -43,8 +43,21 @@ public NonloadingClassWriter(ClassGroup group, int flags)
 	@Override
 	protected String getCommonSuperClass(String type1, String type2)
 	{
-		ClassFile cf1 = group.findClass(type1),
-			cf2 = group.findClass(type2);
+		// Checking more than this wouldn't make any sense
+		// Object has no super class, and RS api is guaranteed to be interfaces, which always extend from Object
+		// some rl api classes however ARE actual classes, so we can't just assume interface, for the slim chance
+		// we've got rl api on classpath. We could check all implemented interfaces in group, but that means you end up
+		// with Object as super class anyway, just like if you just let the Class.forName call throw.
+		// (maybe we could if we had a better package structure...)
+		if (type1.equals("java/lang/Object")
+			|| type2.equals("java/lang/Object")
+			|| type1.startsWith("net/runelite/rs/api/RS")
+			|| type2.startsWith("net/runelite/rs/api/RS")
+		)
+			return "java/lang/Object";
+
+		ClassFile cf1 = group.findClass(type1);
+		ClassFile cf2 = group.findClass(type2);
 
 		if (cf1 == null && cf2 == null)
 		{
@@ -62,10 +75,11 @@ protected String getCommonSuperClass(String type1, String type2)
 
 		if (cf1 != null && cf2 != null)
 		{
-			for (ClassFile c = cf1; c != null; c = c.getParent())
-				for (ClassFile c2 = cf2; c2 != null; c2 = c2.getParent())
-					if (c == c2)
-						return c.getName();
+			if (!(cf1.isInterface() || cf2.isInterface()))
+				for (ClassFile c = cf1; c != null; c = c.getParent())
+					for (ClassFile c2 = cf2; c2 != null; c2 = c2.getParent())
+						if (c == c2)
+							return c.getName();
 
 			return "java/lang/Object";
 		}
@@ -80,21 +94,17 @@ protected String getCommonSuperClass(String type1, String type2)
 		}
 		else
 		{
-			assert cf2 == null;
 			found = cf1;
 			other = type2;
 		}
 
 		ClassFile prev = null;
 
 		for (ClassFile c = found; c != null; c = c.getParent())
-		{
-			prev = c;
-
-			if (c.getName().equals(other))
+			if ((prev = c).getSuperName().equals(other))
 				return other;
-		}
 
+		// This should pretty much never be hit, right?
 		return super.getCommonSuperClass(prev.getSuperName(), other);
 	}
 }