Disable VK overscroll for login/out-of-box.

chrome/browser/chromeos/login/ui/login_display.h

Index: chrome/browser/chromeos/login/ui/login_display.h
diff --git a/chrome/browser/chromeos/login/ui/login_display.h b/chrome/browser/chromeos/login/ui/login_display.h
index eb727e8f68bdd009d0be0644815249b74e87909b..7e6197b5d99206f8a5da05b079e3a7ee09065236 100644
--- a/chrome/browser/chromeos/login/ui/login_display.h
+++ b/chrome/browser/chromeos/login/ui/login_display.h
@@ -168,6 +168,12 @@ class LoginDisplay : public RemoveUserDelegate {
   // Hides or shows login UI control bar with [Shut down] / [Add user] buttons.
   virtual void ShowControlBar(bool show) = 0;
 
+  // Sets the virtual keyboard state.
+  virtual void SetKeyboardState(bool shown) = 0;
+
+  // Sets the WebUI client area size (based on display dimensions).
+  virtual void SetClientAreaSize(int width, int height) = 0;
+
   gfx::Rect background_bounds() const { return background_bounds_; }
   void set_background_bounds(const gfx::Rect& background_bounds) {
     background_bounds_ = background_bounds;