Fix Top Menu Url

This fixes it so that if it provides a url with https:// then it will use it
instead of building from the base url and then adding a extra url.

Bug: Issue 9772
Change-Id: I984204249425ba44c432794f804e0357cd5a2cfb

polygerrit-ui/app/elements/shared/gr-dropdown/gr-dropdown.js

@@ -229,7 +229,7 @@
       if (typeof link.url === 'undefined') {
         return '';
       }
-      if (link.target) {
+      if (link.target || !link.url.startsWith('/')) {
         return link.url;
       }
       return this._computeRelativeURL(link.url);

polygerrit-ui/app/elements/shared/gr-dropdown/gr-dropdown_test.html

@@ -72,6 +72,12 @@ limitations under the License.
     });
 
     test('link URLs', () => {
+      assert.equal(
+          element._computeLinkURL({url: 'http://example.com/test'}),
+          'http://example.com/test');
+      assert.equal(
+          element._computeLinkURL({url: 'https://example.com/test'}),
+          'https://example.com/test');
       assert.equal(
           element._computeLinkURL({url: '/test'}),
           '//' + window.location.host + '/test');