Remove implementation of Panels on OSes other than ChromeOS.

chrome/browser/extensions/api/management/management_apitest.cc

Index: chrome/browser/extensions/api/management/management_apitest.cc
diff --git a/chrome/browser/extensions/api/management/management_apitest.cc b/chrome/browser/extensions/api/management/management_apitest.cc
index 760a7fb345e5c413677fac0bbbfa43844f967275..281ebe3743280a756130ccff05ae9b0e7d9558a5 100644
--- a/chrome/browser/extensions/api/management/management_apitest.cc
+++ b/chrome/browser/extensions/api/management/management_apitest.cc
@@ -46,11 +46,6 @@ Browser* FindOtherBrowser(Browser* browser) {
 
 class ExtensionManagementApiTest : public ExtensionApiTest {
  public:
-  void SetUpCommandLine(base::CommandLine* command_line) override {
-    ExtensionApiTest::SetUpCommandLine(command_line);
-    command_line->AppendSwitch(switches::kEnablePanels);
-  }
-
   virtual void LoadExtensions() {
     base::FilePath basedir = test_data_dir_.AppendASCII("management");