KtLightMethod: isVarArgs() does not trigger exact delegate computation

compiler/testData/asJava/lightClasses/VarArgs.kt

@@ -0,0 +1,12 @@
+// C
+
+class C {
+
+    fun f(vararg i: Int) {
+
+    }
+
+    fun p(i: Int, vararg s: String) {
+
+    }
+}