add test to check that user name is properly escaped

test/spec/ui/account.js

@@ -0,0 +1,23 @@
+describe('iD.uiAccount', function () {
+    it('properly escapes user name', function() {
+        var selection = d3.select('body').append('div');
+        var osmConnectionMock = {
+            authenticated: () => true,
+            userDetails: (callback) => {
+                callback(null, {
+                    display_name: 'x<br>y'
+                });
+            },
+            userURL: () => '',
+            on: (handler, callback) => {
+                if (handler === 'change.account') {
+                    onChangeAccountHandler = callback;
+                }
+            }
+        };
+        var onChangeAccountHandler;
+        iD.uiAccount({ connection: () => osmConnectionMock })(selection);
+        onChangeAccountHandler.call();
+        expect(selection.select('.userInfo span.label').text()).to.equal('x<br>y');
+    });
+});