Restrict chrome.runtime.setUninstallURL to http(s)

chrome/test/data/extensions/api_test/runtime/uninstall_url/test.js

 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // extension api test
 // browser_tests.exe --gtest_filter=ExtensionApiTest.ChromeRuntimeUninstallURL
 
 var pass = chrome.test.callbackPass;
 var uninstall_url = 'http://www.google.com/';
 var sets_uninstall_url = 'Sets Uninstall Url';
@@ skipping 10 matching lines @@
                 chrome.test.assertEq(tabs[0].url, uninstall_url);
               }));
             }));
           }));
           uninstalled = true;
           break;
         }
       }
       chrome.test.assertTrue(uninstalled);
     });
+  },
+  function setEmptyUrl() {
+    chrome.runtime.setUninstallURL('', function() {
+      chrome.test.assertNoLastError();
+      chrome.test.succeed();
+    });
+  },
+  function uninstallInvalidURLNonHttpOrHttps() {
+    chrome.runtime.setUninstallURL('chrome://newtab', function() {
+      chrome.test.assertLastError('Invalid URL: "chrome://newtab".');
+      chrome.test.succeed();
+    });
   }
 ]);