Cleanup: supervised_user_theme.cc should not be built if themes are not enabled.

chrome/chrome_browser.gypi

Index: chrome/chrome_browser.gypi
diff --git a/chrome/chrome_browser.gypi b/chrome/chrome_browser.gypi
index 2cd9afe8baab21bfe29d4ab06a59e86e685469be..bcf350dffbf9ef6b1ed31d1a38034cb30cf622c3 100644
--- a/chrome/chrome_browser.gypi
+++ b/chrome/chrome_browser.gypi
@@ -2348,12 +2348,14 @@
       'browser/supervised_user/supervised_user_sync_service_factory.cc',
       'browser/supervised_user/supervised_user_sync_service_factory.h',
       'browser/supervised_user/supervised_user_sync_service_observer.h',
-      'browser/supervised_user/supervised_user_theme.cc',
-      'browser/supervised_user/supervised_user_theme.h',
       'browser/supervised_user/supervised_user_url_filter.cc',
       'browser/supervised_user/supervised_user_url_filter.h',
       'browser/supervised_user/supervised_users.h',
     ],
+    'chrome_browser_supervised_user_and_themes_sources': [
+      'browser/supervised_user/supervised_user_theme.cc',
+      'browser/supervised_user/supervised_user_theme.h',
+    ],
     'chrome_browser_undo_sources': [
       'browser/undo/bookmark_undo_service.cc',
       'browser/undo/bookmark_undo_service_factory.cc',
@@ -3428,6 +3430,9 @@
         ['enable_managed_users==1', {
           'sources': [ '<@(chrome_browser_supervised_user_sources)' ],
         }],
+        ['enable_managed_users==1 and enable_themes==1', {
+          'sources': [ '<@(chrome_browser_supervised_user_and_themes_sources)' ],
+        }],
         ['enable_webrtc==1', {
           'sources': [ '<@(chrome_browser_webrtc_sources)' ]
         }],