Add testcase for with(symbol) fix.

tests/mini/with3.d

@@ -0,0 +1,21 @@
+enum fields 
+{ 
+    FIELD1, 
+    FIELD2 
+} 
+ 
+fields find_field(fields f) { 
+    with(fields) { 
+        switch(f) { 
+        case FIELD1:  
+	  return FIELD1;
+        default: 
+	  return FIELD2;
+        } 
+    } 
+} 
+ 
+void main() { 
+  assert(find_field(fields.FIELD1) == fields.FIELD1);
+  assert(find_field(fields.FIELD2) == fields.FIELD2);
+}