Fix serviceworker default registration scope.

LayoutTests/http/tests/serviceworker/registration.html

Index: LayoutTests/http/tests/serviceworker/registration.html
diff --git a/LayoutTests/http/tests/serviceworker/registration.html b/LayoutTests/http/tests/serviceworker/registration.html
index 60bafe9fdc95430b71b0c9dd74d5af79f7075335..149e96cf01ceae19428d5d2b2d113c642687b00b 100644
--- a/LayoutTests/http/tests/serviceworker/registration.html
+++ b/LayoutTests/http/tests/serviceworker/registration.html
@@ -44,6 +44,24 @@
 }());
 
 (function() {
+    var t = async_test('Registering default scope');

[jsbell, 2014/06/18 17:57:03]

There's a test for the default scope in serviceworkerglobalscope-scope.html
that's apparently passing even with this change. :(

I think the problem with that test and with this one is that '*' and '/*' are
not distinguishable, since the test is running at the root level of the server,
so String(new URL(document.location, '*')) === String(new URL(document.location,
'/*'))

Does this test fail if the C++ change is not present?

If not, we should add a test where the registration is done not in the root,
e.g. an iframe in 'resources/XXXX.html' registers; that should be able to
distinguish '*' from '/*'

[xiang, 2014/06/19 04:57:45]

The default scope tests in serviceworkerglobalscope-scope.html and
serviceworkerobject-scope.html will fail after this change:
FAIL Verify the scope property: default assert_equals: Worker should see the
scope on eval. expected "http://127.0.0.1:8000/serviceworker/*" but got
"http://127.0.0.1:8000/*"

Think the "relative_path = test_name[len(self.HTTP_DIR):]" in port/driver.py can
make these tests running in 'serviceworker/xxx.html' pattern.

I will remove this test and use those two instead.

+    t.step(function() {
+        navigator.serviceWorker.register('resources/registration-worker.js'
+        ).then(
+            t.step_func(function(worker) {
+                var default_scope = '/*';
+                assert_equals(worker.scope, location.origin + default_scope,
+                              'Registration scope should default to "/*".');
+                service_worker_unregister_and_done(t, default_scope);
+            }),
+            t.step_func(function(reason) { 
+                assert_unreached('Registration should succeed, but failed: ' + reason.name);
+            })
+        );
+    });
+}());
+
+(function() {
     var t = async_test('Registering script outside domain');
     t.step(function() {
         navigator.serviceWorker.register(