Attempt re-enable of Security Page tests on MacOS

A large refactoring of logic on the security page occurred after the
CrSettingsSecurityPageV3 tests were disabled on MacOS.

This CL re-enables the test on disabled platform in the expectation that
previous changes have fixed MacOS platform specific flakes.

Bug: 1081908
Change-Id: I79f8fcd1f408913b0d99d0fe2a8efe697ea86ad7
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2463608Reviewed-by: Sean Harrison <harrisonsean@chromium.org>
Commit-Queue: Theodore Olsauskas-Warren <sauski@google.com>
Cr-Commit-Position: refs/heads/master@{#819334}

chrome/test/data/webui/settings/cr_settings_v3_browsertest.js

@@ -500,6 +500,7 @@ TEST_F('CrSettingsAdvancedPageV3Test', 'MAYBE_Load', function() {
  ['SearchPage', 'search_page_test.js'],
  ['Search', 'search_settings_test.js'],
  ['SecurityKeysSubpage', 'security_keys_subpage_test.js'],
+ ['SecurityPage', 'security_page_test.js'],
  ['SecureDns', 'secure_dns_test.js'],
  // Copied from P2 test: Disabled for flakiness, see https://crbug.com/1061249
  ['SiteData', 'site_data_test.js', 'DISABLED_All'],
@@ -529,8 +530,6 @@ GEN('#endif  // defined(OS_CHROMEOS)');
 
 GEN('#if !defined(OS_MAC)');
 [['EditDictionaryPage', 'edit_dictionary_page_test.js'],
- // TODO(https://crbug.com/1081908): Flaky on Mac. Fix and re-enable.
- ['SecurityPage', 'security_page_test.js'],
 ].forEach(test => registerTest(...test));
 GEN('#endif  //!defined(OS_MAC)');