Fix bug in CompareNil IC

test/mjsunit/compare-nil.js

Index: test/mjsunit/compare-nil.js
diff --git a/test/mjsunit/regress/regress-crbug-173974.js b/test/mjsunit/compare-nil.js
similarity index 92%
copy from test/mjsunit/regress/regress-crbug-173974.js
copy to test/mjsunit/compare-nil.js
index 905bd6058a0ad0fe2ebe10e4c7dafbe9945cbe3b..0895a31fb80cbe697b678eaa1005926d7d65829f 100644
--- a/test/mjsunit/regress/regress-crbug-173974.js
+++ b/test/mjsunit/compare-nil.js
@@ -27,10 +27,10 @@
 
 // Flags: --allow-natives-syntax
 
-function f() {
-  var count = "";
-  count[0] --;
+function test(v) {
+  return (v == null);
 }
-f();
-%OptimizeFunctionOnNextCall(f);
-f();
+assertFalse(test(true));
+assertFalse(test(true));
+assertTrue(test(null));
+assertTrue(test(null));