[Sync Setup UI] Separate stepping the SyncSetupWizard from syncSetup page navigation.

chrome/browser/ui/webui/sync_setup_handler.h

Index: chrome/browser/ui/webui/sync_setup_handler.h
diff --git a/chrome/browser/ui/webui/sync_setup_handler.h b/chrome/browser/ui/webui/sync_setup_handler.h
index e1ac14dc1800d2fae3d587db5b16fdaa4d59c32b..d77ae73bbb335db51e83315f25f962ae767495a9 100644
--- a/chrome/browser/ui/webui/sync_setup_handler.h
+++ b/chrome/browser/ui/webui/sync_setup_handler.h
@@ -81,6 +81,10 @@ class SyncSetupHandler : public GaiaOAuthConsumer,
 
   SyncSetupFlow* flow() { return flow_; }
 
+  // Subclasses must implement to step the SyncSetupWizard to the correct state
+  // before showing the Setup UI.
+  virtual void StepWizardForShowSetupUI() = 0;
+
   // Subclasses must implement this to show the setup UI that's appropriate
   // for the page this is contained in.
   virtual void ShowSetupUI() = 0;