Converted policy_prefs_ui.py pyauto test to a browser_test.

chrome/browser/automation/testing_automation_provider.h

Index: chrome/browser/automation/testing_automation_provider.h
diff --git a/chrome/browser/automation/testing_automation_provider.h b/chrome/browser/automation/testing_automation_provider.h
index 33e1633cafc3d77b7db6e567ebcf96739594cd93..41d3ecdda68270573fe10d3bdb3f25ba5ff65fc4 100644
--- a/chrome/browser/automation/testing_automation_provider.h
+++ b/chrome/browser/automation/testing_automation_provider.h
@@ -1373,16 +1373,6 @@ class TestingAutomationProvider : public AutomationProvider,
   void CreateNewAutomationProvider(base::DictionaryValue* args,
                                    IPC::Message* reply_message);
 
-  // Gets a list of supported policies. The output is a map of policy name to
-  // its value type.
-  // Example:
-  //   input: none
-  //   output: { "ShowHomeButton": "bool",
-  //             "DefaultSearchProviderSearchURL": "str"
-  //           }
-  void GetPolicyDefinitionList(base::DictionaryValue* args,
-                               IPC::Message* reply_message);
-
   // Triggers a policy update on the platform and cloud providers, if they
   // exist. Returns after the update notifications are received.
   // Example: