Migrated several tests from blink to V8 repository.

test/webkit/dfg-peephole-compare-final-object-to-final-object-or-other-when-proven-final-object.js

Index: test/webkit/dfg-peephole-compare-final-object-to-final-object-or-other-when-proven-final-object.js
diff --git a/test/webkit/concat-while-having-a-bad-time.js b/test/webkit/dfg-peephole-compare-final-object-to-final-object-or-other-when-proven-final-object.js
similarity index 71%
copy from test/webkit/concat-while-having-a-bad-time.js
copy to test/webkit/dfg-peephole-compare-final-object-to-final-object-or-other-when-proven-final-object.js
index dfda1e08a0b36194b787a44ee12a9693acd8aeaf..5e27539b1710b08bd2d2ec8e019ff855500e62ce 100644
--- a/test/webkit/concat-while-having-a-bad-time.js
+++ b/test/webkit/dfg-peephole-compare-final-object-to-final-object-or-other-when-proven-final-object.js
@@ -22,10 +22,24 @@
 // 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 that the peephole CompareEq optimization for the case where one side is predicted final object and the other side is predicted either final object or other (i.e. null or undefined) doesn't assert when the other side is also proven final object."
 );
 
-Object.defineProperty(Array.prototype, 0, { writable: false });
-shouldBe("[42].concat()", "[42]");
+function foo(a, b) {
+    var result = [];
+    result.push(b.f);
+    if (a == b)
+        result.push(true);
+    else
+        result.push(false);
+    return result;
+}
 
+for (var i = 0; i < 100; ++i) {
+    if (i%2) {
+        var o = {f:42};
+        shouldBe("foo(o, o)", "[42, true]");
+    } else
+        shouldThrow("foo({f:42}, null)");
+}