Remove unnecessary code - this feature is enabled on Mac

Bug: 1012108
Change-Id: Ic9a38aaae92ea1592a244283304608b429cf7bbc
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2092933
Commit-Queue: Aaron Leventhal <aleventhal@chromium.org>
Auto-Submit: Mason Freed <masonfreed@chromium.org>
Reviewed-by: Aaron Leventhal <aleventhal@chromium.org>
Cr-Commit-Position: refs/heads/master@{#748402}

content/browser/accessibility/dump_accessibility_browsertest_base.cc

@@ -117,11 +117,6 @@ void DumpAccessibilityTestBase::SetUp() {
   enabled_features.emplace_back(
       features::kEnableAccessibilityExposeDisplayNone);
 
-  // Enable the FormControlsRefresh feature to make sure the
-  // accessibility tree is the same across platforms.
-  // TODO(1012108): remove this once Mac is also enabled by default.
-  enabled_features.emplace_back(features::kFormControlsRefresh);
-
   enabled_features.emplace_back(blink::features::kPortals);
 
   // TODO(dmazzoni): DumpAccessibilityTree expectations are based on the