256458: test and fix: better message for if() pointcut anno style problems

tests/bugs163/pr256458/Code.java

@@ -0,0 +1,7 @@
+import org.aspectj.lang.annotation.*;
+
+@Aspect
+public class Code {
+  @Before("if(37!=42)")
+  public void runme() {}
+}

tests/bugs163/pr256458/Code2.java

@@ -0,0 +1,10 @@
+import org.aspectj.lang.annotation.*;
+
+@Aspect
+public class Code2 {
+
+   @Around("execution(* Code.*(..)) && if(java.lang.System.currentTimeMillis() > 1)")
+   public void foo() {
+   }
+
+}