core: ClassModifier: Don't skip methods with SKIP_FIRST_ARG attr

Skipping those methods on class refresh leads to "M.this = r1;" like
assigments appears in the inner class constructors.

Unsure is this saint or not.

jadx-core/src/main/java/jadx/core/dex/visitors/ClassModifier.java

@@ -105,7 +105,7 @@ public class ClassModifier extends AbstractVisitor {
 			return false;
 		}
 		List<RegisterArg> args = mth.getArgRegs();
-		if (args.isEmpty() || mth.contains(AFlag.SKIP_FIRST_ARG)) {
+		if (args.isEmpty()) {
 			return false;
 		}
 		RegisterArg arg = args.get(0);