[Blink-Workers]Set verbosity of the external exception handler.

third_party/WebKit/LayoutTests/fast/workers/worker-constructor.html

Index: third_party/WebKit/LayoutTests/fast/workers/worker-constructor.html
diff --git a/third_party/WebKit/LayoutTests/fast/workers/worker-constructor.html b/third_party/WebKit/LayoutTests/fast/workers/worker-constructor.html
index 38f5423ada7e4a79a6fe1f080df1c0a34905139e..8120f2729fec3ac2426ad345296ea1a618c79152 100644
--- a/third_party/WebKit/LayoutTests/fast/workers/worker-constructor.html
+++ b/third_party/WebKit/LayoutTests/fast/workers/worker-constructor.html
@@ -11,9 +11,9 @@ var testCases = [
     "testArgumentException",
     "testRecursiveWorkerCreation",
     "testNoArgument",
-    "testEmptyScriptUrl",
     "testInvalidScriptUrl",
     "testNotExistentScriptUrl",
+    "testEmptyScriptUrl",

[nhiroki, 2016/07/26 01:59:11]

Why did you move this test case?

[sivag, 2016/07/27 13:20:52]

In these set of tests only 2 tests throw worker.onerror testNotExistentScriptUrl
and testEmptyScriptUrl", but here when verbose is enabled  and the order of call
is 

testEmptyScriptUrl
...
testNotExistentScriptUrl

in both cases testEmptyScriptUrl functions worker.onerror is getting
printed.changing the order as above works fine.Initially i thought we are
executing the next test case in onerror by calling runNextTest(); which might be
causing this, but i tried calling this after the try catch for all test cases
still the same issue exists.

I am trying to figure out why this happens.

[sivag, 2016/07/29 09:29:32]

After enabling verbose the order of test is getting effected.
When test [1] new Worker("") gets called before test [2] new
Worker("emptyscript.js")
in both cases test[1] onError is getting called.

If i make test [1] to  new Worker("invalid.js") , with out changing the order
the respective onerror functions of [1][2] get called.

Any pointers, how should we proceed further here?

     "testSuccessWorkerCreation",
 ];
 var testIndex = 0;