Implement sidebar support for extension action popups

chrome/browser/extensions/extension_system_impl.cc

Index: chrome/browser/extensions/extension_system_impl.cc
diff --git a/chrome/browser/extensions/extension_system_impl.cc b/chrome/browser/extensions/extension_system_impl.cc
index 31a79a886f3ac8f4404dcf15cc23100e21049c29..4cd36acf17e408da025a61a55ccacf81ac8fd5d1 100644
--- a/chrome/browser/extensions/extension_system_impl.cc
+++ b/chrome/browser/extensions/extension_system_impl.cc
@@ -26,6 +26,7 @@
 #include "chrome/browser/extensions/navigation_observer.h"
 #include "chrome/browser/extensions/shared_module_service.h"
 #include "chrome/browser/extensions/shared_user_script_master.h"
+#include "chrome/browser/extensions/sidebar_manager.h"
 #include "chrome/browser/extensions/state_store_notification_observer.h"
 #include "chrome/browser/extensions/unpacked_installer.h"
 #include "chrome/browser/profiles/profile.h"
@@ -565,4 +566,15 @@ void ExtensionSystemImpl::UnregisterExtensionWithRequestContexts(
       base::Bind(&InfoMap::RemoveExtension, info_map(), extension_id, reason));
 }
 
+SidebarManager* ExtensionSystemImpl::sidebar_manager() {
+  if (!sidebar_manager_)
+    CreateSidebarManager();
+  return sidebar_manager_.get();
+}
+
+void ExtensionSystemImpl::CreateSidebarManager() {
+  DCHECK(sidebar_manager_.get() == nullptr);
+  sidebar_manager_.reset(new SidebarManager());
+}
+
 }  // namespace extensions