Use OS_WIN instead of OS_WINDOWS to disable flaky...

Use OS_WIN instead of OS_WINDOWS to disable flaky ContentSettingsExceptionAreaWebUITest.testOpenContentSettingsExceptionArea

BUG=588586
TBR=dbeam@chromium.org,pkasting@chromium.org

Review-Url: https://codereview.chromium.org/2032533002
Cr-Commit-Position: refs/heads/master@{#397152}

chrome/browser/ui/webui/options/content_settings_exception_area_browsertest.js

@@ -19,7 +19,7 @@ ContentSettingsExceptionAreaWebUITest.prototype = {
 };
 
 // See crbug.com/579666 for OS_LINUX and crbug.com/588586 for Windows.
-GEN('#if defined(OS_CHROMEOS) || defined(OS_LINUX) || defined(OS_WINDOWS)');
+GEN('#if defined(OS_CHROMEOS) || defined(OS_LINUX) || defined(OS_WIN)');
 GEN('#define MAYBE_testOpenContentSettingsExceptionArea ' +
         'DISABLED_testOpenContentSettingsExceptionArea');
 GEN('#else');