Panels back behind a flag.

chrome/browser/ui/panels/panel_manager.h

Index: chrome/browser/ui/panels/panel_manager.h
diff --git a/chrome/browser/ui/panels/panel_manager.h b/chrome/browser/ui/panels/panel_manager.h
index c36f8c7d592850b5d0e27f5d260e629cd2bd0d74..06cf850ba25b07acd2a869e09b77903636772b1c 100644
--- a/chrome/browser/ui/panels/panel_manager.h
+++ b/chrome/browser/ui/panels/panel_manager.h
@@ -28,6 +28,9 @@ class PanelManager : public AutoHidingDesktopBar::Observer {
   // Returns a single instance.
   static PanelManager* GetInstance();
 
+  // Returns true if panels should be used for the extension.
+  static bool ShouldUsePanels(const std::string& extension_id);
+
   // Called when the display is changed, i.e. work area is updated.
   void OnDisplayChanged();