Import web-platform-tests/webstorage

LayoutTests/imported/web-platform-tests/webstorage/event_case_sensitive.js

+testStorages(function(storageString) {
+    async_test(function(t) {
+        assert_true(storageString in window, storageString + " exist");
+        var storage = window[storageString];
+        t.add_cleanup(function() { storage.clear() });
+
+        storage.clear();
+        assert_equals(storage.length, 0, "storage.length");
+        storage.foo = "test";
+
+        runAfterNStorageEvents(t.step_func(step1), 1);
+
+        function step1(msg)
+        {
+            storageEventList = new Array();
+            storage.foo = "test";
+
+            runAfterNStorageEvents(t.step_func(step2), 0);
+        }
+
+        function step2(msg)
+        {
+            if(msg != undefined) {
+                assert_unreached(msg);
+            }
+            assert_equals(storageEventList.length, 0);
+
+            storage.foo = "TEST";
+
+            runAfterNStorageEvents(t.step_func(step3), 1);
+        }
+
+        function step3(msg)
+        {
+            if(msg != undefined) {
+                assert_unreached(msg);
+            }
+            assert_equals(storageEventList.length, 1);
+
+            t.done();
+        }
+    }, storageString + " storage events fire even when only the case of the value changes.");
+});