dfa: store CCE state in visitor, not runner: the latter is reused which can result in multiple warning

java/java-tests/testData/inspection/dataFlow/fixture/DoubleCCEWarning.java

@@ -0,0 +1,21 @@
+class X {
+  public static void main(Object result) {
+    final boolean varargs = result instanceof Intf;
+    new Runnable() {
+      public void run() { }
+    };
+    Intf a = (<warning descr="Casting 'result' to 'Intf' may produce 'java.lang.ClassCastException'">Intf</warning>)result;
+  }
+
+  public static void main2(Object result) {
+    final boolean varargs = result instanceof Intf;
+    if (!varargs) return;
+    new Runnable() {
+      public void run() { }
+    };
+    if (<warning descr="Condition 'result instanceof Intf' is always 'true'">result instanceof Intf</warning>) {
+      System.out.println();
+    }
+  }
+}
+interface Intf {}