Add |extra_info| parameter for browser creation (fixes issue #1088)

The optional |extra_info| parameter provides an opportunity to specify extra
information specific to the created browser that will be passed to
CefRenderProcessHandler::OnBrowserCreated() in the render process.

tests/cefclient/browser/browser_window.h

@@ -60,6 +60,7 @@ class BrowserWindow : public ClientHandler::Delegate {
   virtual void CreateBrowser(ClientWindowHandle parent_handle,
                              const CefRect& rect,
                              const CefBrowserSettings& settings,
+                             CefRefPtr<CefDictionaryValue> extra_info,
                              CefRefPtr<CefRequestContext> request_context) = 0;
 
   // Retrieve the configuration that will be used when creating a popup window.