Make extensions that desire to act pop out if in overflow

chrome/browser/ui/views/toolbar/browser_action_view.h

Index: chrome/browser/ui/views/toolbar/browser_action_view.h
diff --git a/chrome/browser/ui/views/toolbar/browser_action_view.h b/chrome/browser/ui/views/toolbar/browser_action_view.h
index 8f864c7739d7178552acab68f704036e463b5966..bf4e8d7e6ee7d2cd5f159552fb13306857b4305c 100644
--- a/chrome/browser/ui/views/toolbar/browser_action_view.h
+++ b/chrome/browser/ui/views/toolbar/browser_action_view.h
@@ -42,7 +42,7 @@ class BrowserActionView : public views::MenuButton,
   class Delegate : public views::DragController {
    public:
     // Returns the current web contents.
-    virtual content::WebContents* GetCurrentWebContents() = 0;
+    virtual content::WebContents* GetCurrentWebContents() const = 0;
 
     // Whether the container for this button is shown inside a menu.
     virtual bool ShownInsideMenu() const = 0;