fix: Remove more exception obfuscation

Author: Pazaz

src/main/java/rs/lostcity/deob/bytecode/transform/openrs2/ExceptionObfuscationTransformer.java

@@ -7,6 +7,7 @@
 import rs.lostcity.asm.transform.Transformer;
 
 import java.util.List;
+import java.util.Objects;
 
 /**
  * A [Transformer] responsible for removing [ZKM](http://www.zelix.com/klassmaster/)'s
@@ -26,19 +27,25 @@ public void preTransform(List<ClassNode> classes) {
     @Override
     public boolean transformCode(List<ClassNode> classes, ClassNode clazz, MethodNode method) {
         for (var insn : method.instructions) {
-            if (insn.getOpcode() != Opcodes.ATHROW) {
-                continue;
-            }
-
-            var foundTryCatch = method.tryCatchBlocks.removeIf(tryCatch ->
-                InsnNodeUtil.getNextReal(tryCatch.handler).equals(insn));
-
-            if (foundTryCatch) {
-                method.instructions.remove(insn);
-                handlers++;
+            if (insn.getOpcode() == Opcodes.ATHROW) {
+                // redundant throw
+                var foundTryCatch = method.tryCatchBlocks.removeIf(tryCatch ->
+                    InsnNodeUtil.getNextReal(tryCatch.handler).equals(insn));
+
+                if (foundTryCatch) {
+                    method.instructions.remove(insn);
+                    handlers++;
+                }
             }
         }
 
+        int before = method.tryCatchBlocks.size();
+        // todo: this may result in synchronized blocks going unused
+        method.tryCatchBlocks.removeIf(tryCatch -> tryCatch.type == null);
+        // todo: confirm this is fine, early clients don't need throwable for any legitimate use
+        method.tryCatchBlocks.removeIf(tryCatch -> Objects.equals(tryCatch.type, "java/lang/Throwable"));
+        handlers += before - method.tryCatchBlocks.size();
+
         return false;
     }