MD Settings: don't allow supervised users to switch to GTK+ theme

chrome/browser/resources/settings/appearance_page/appearance_page.js

Index: chrome/browser/resources/settings/appearance_page/appearance_page.js
diff --git a/chrome/browser/resources/settings/appearance_page/appearance_page.js b/chrome/browser/resources/settings/appearance_page/appearance_page.js
index bde7e1c8e9b5e54768aabeb6f92cb1e6842cbc34..f6468a2c3e67ed7728125b9c224aafc7d6189701 100644
--- a/chrome/browser/resources/settings/appearance_page/appearance_page.js
+++ b/chrome/browser/resources/settings/appearance_page/appearance_page.js
@@ -173,23 +173,32 @@ Polymer({
   },
 
   /**
-   * @param {string} themeId
-   * @param {boolean} useSystemTheme
    * @return {boolean} Whether to show the "USE CLASSIC" button.
    * @private
    */
-  showUseClassic_: function(themeId, useSystemTheme) {
-    return !!themeId || useSystemTheme;
+  showUseClassic_: function() {
+    if (this.useSystemTheme_)
+      return true;
+    return !!this.get('prefs.extensions.theme.id.value');

[dpapad, 2016/10/18 17:49:34]

Nit:
return this.useSystemTheme_ || !!this.get('prefs.extensions.theme.id.value');

[Dan Beam, 2016/10/18 18:59:52]

see updated code

   },
 
   /**
-   * @param {string} themeId
-   * @param {boolean} useSystemTheme
    * @return {boolean} Whether to show the "USE GTK+" button.
    * @private
    */
-  showUseSystem_: function(themeId, useSystemTheme) {
-    return !!themeId || !useSystemTheme;
+  showUseSystem_: function() {
+    if (this.useSystemTheme_ || loadTimeData.getBoolean('isSupervised'))
+      return false;
+    return !!this.get('prefs.extensions.theme.id.value');
+  },
+
+  /**
+   * @return {boolean} Whether to show the secondary area where "USE CLASSIC"
+   *     and "USE GTK+" buttons live.
+   * @private
+   */
+  showThemesSecondary_: function() {
+    return this.showUseClassic_() || this.showUseSystem_();
   },
 
   /** @private */