commit b0634cabdaf90e786185402d57d2029940dd2f16
Author: Joel Pittet <joel@pittet.ca>
Date:   Wed Oct 2 12:00:43 2013 -0700

    removed theme function

diff --git a/core/modules/system/tests/modules/theme_test/theme_test.module b/core/modules/system/tests/modules/theme_test/theme_test.module
index f52d74a..84a1924 100644
--- a/core/modules/system/tests/modules/theme_test/theme_test.module
+++ b/core/modules/system/tests/modules/theme_test/theme_test.module
@@ -114,13 +114,6 @@ function theme_test_page_alter(&$page) {
 }
 
 /**
- * Theme function for testing theme('theme_test_foo').
- */
-function theme_theme_test_foo($variables) {
-  return $variables['foo'];
-}
-
-/**
  * Theme function for testing theme('theme_test_function_template_override').
  */
 function theme_theme_test_function_template_override($variables) {