Add a11y virtual keyboard icon when a11y VK is enabled

ui/keyboard/keyboard_controller.h

Index: ui/keyboard/keyboard_controller.h
diff --git a/ui/keyboard/keyboard_controller.h b/ui/keyboard/keyboard_controller.h
index fecbe1618acdfc9e5459a6a9e8f7e07ba59a9745..f7c5f4450b18ff9ce881038c1cb8f1324e4be469 100644
--- a/ui/keyboard/keyboard_controller.h
+++ b/ui/keyboard/keyboard_controller.h
@@ -79,6 +79,9 @@ class KEYBOARD_EXPORT KeyboardController : public ui::InputMethodObserver,
 
   void set_lock_keyboard(bool lock) { lock_keyboard_ = lock; }
 
+  // Force the keyboard to show up if not showing and lock the keyboard.
+  void ShowAndLockKeyboard();
+
  private:
   // For access to Observer methods for simulation.
   friend class KeyboardControllerTest;