[MD settings] show icon when slider controlled by something

chrome/test/data/webui/cr_elements/cr_elements_browsertest.js

Index: chrome/test/data/webui/cr_elements/cr_elements_browsertest.js
diff --git a/chrome/test/data/webui/cr_elements/cr_elements_browsertest.js b/chrome/test/data/webui/cr_elements/cr_elements_browsertest.js
index 395657290495d9cb41fd0abd4b4f0852b16e499f..a10f211a21c472679c9468d328c801ecb30b43c6 100644
--- a/chrome/test/data/webui/cr_elements/cr_elements_browsertest.js
+++ b/chrome/test/data/webui/cr_elements/cr_elements_browsertest.js
@@ -127,6 +127,7 @@ CrElementsSliderTest.prototype = {
 
   /** @override */
   extraLibraries: CrElementsBrowserTest.prototype.extraLibraries.concat([
+    'settings_private_test_constants.js',
     'cr_slider_tests.js',
   ]),
 };
@@ -218,6 +219,7 @@ CrElementsPolicyPrefIndicatorTest.prototype = {
 
   /** @override */
   extraLibraries: CrElementsBrowserTest.prototype.extraLibraries.concat([
+    'settings_private_test_constants.js',
     'cr_policy_strings.js',
     'cr_policy_pref_indicator_tests.js',
   ]),