Migrated several tests from blink to V8 repository.

test/webkit/dfg-to-string-side-effect-clobbers-toString.js

Index: test/webkit/dfg-to-string-side-effect-clobbers-toString.js
diff --git a/test/webkit/concat-while-having-a-bad-time.js b/test/webkit/dfg-to-string-side-effect-clobbers-toString.js
similarity index 71%
copy from test/webkit/concat-while-having-a-bad-time.js
copy to test/webkit/dfg-to-string-side-effect-clobbers-toString.js
index dfda1e08a0b36194b787a44ee12a9693acd8aeaf..5facc60a471c0d9b26252000cdded64fb9afa43f 100644
--- a/test/webkit/concat-while-having-a-bad-time.js
+++ b/test/webkit/dfg-to-string-side-effect-clobbers-toString.js
@@ -22,10 +22,19 @@
 // SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 description(
-"Tests the behavior of Array.prototype.concat while the array is having a bad time due to one of the elements we are concatenating."
+"Tests what happens when you do ToString twice, and it has a side effect that clobbers the toString method in between the two ToStrings."
 );
 
-Object.defineProperty(Array.prototype, 0, { writable: false });
-shouldBe("[42].concat()", "[42]");
-
+function foo(s, sideEffect) {
+    var a = String(s);
+    sideEffect(s);
+    var b = String(s);
+    return a + b;
+}
 
+var count = 0;
+for (var i = 0; i < 200; ++i) {
+    var code = "(function(s) { " + (i < 150 ? "return " + i + ";" : "count++; debug(\"hi!\"); s.toString = function() { return " + i + "; };") + " })";
+    var sideEffect = eval(code);
+    shouldBe("foo(new String(\"hello\"), sideEffect)", i < 150 ? "\"hellohello\"" : "\"hello" + i + "\"");
+}