sendBeacon should throw a TypeError on bad URLs.

third_party/WebKit/LayoutTests/fast/js/exec-state-marking.html

 <p>
 This page tests for a crash due to insufficient marking of ExecStates. If
 the test passes, you'll see a series of PASS messages below.
 </p>
 
 <pre id="console">
 PASS: You didn't crash.
 </pre>
 
 <a id="a"></a>
-
+<script src="../../resources/gc.js"></script>
 <script>
 function log(s)
 {
     document.getElementById("console").appendChild(document.createTextNode(s + "\n"));
 }
 
 function shouldBe(a, aDescription, b)
 {
     if (a == b) {
         log("PASS: " + aDescription + " should be " + b + " and is.");
     } else {
         log("FAIL: " + aDescription + " should be " + b + " but instead is " + a + ".");
     }
 }
 
 function FailureObject()
 {
 }
 
 FailureObject.prototype.toString = function()
 {
     return "FAIL"; // A marker to indicate that an object was collected and then overwritten by a FailureObject.
 }
 
-function gc()
-{
-    if (window.GCController)
-        GCController.collect();
-    else
-        for (var i = 0; i < 10000; ++i) // Allocate a sufficient number of objects to force a GC.
-            new FailureObject;
-}
-
 function gc1()
 {
     var script = document.createElement("script");
     script.appendChild(document.createTextNode("gc()"));
     document.body.appendChild(script);
 }
 
 function gc2()
 {
     var a = document.getElementById("a");
@@ skipping 34 matching lines @@
 
     // Now verify that our activation data wasn't collected, by using it in an interesting way.
     return v1 + v2 + v3 + v4 + v5;
 }
 
 if (window.testRunner)
     testRunner.dumpAsText();
 
 shouldBe(f(), "f()", "12345");
 </script>